Polimetrics

Projection 10/31 9:00 PM
Kerry 60,604,000 50.1% 291 EV
Bush 58,422,000 48.3% 247 EV
Other 1,936,000 1.6%

click here for electoral map

Probability Bush wins each state:
NM 26.5%
IA 29.3%
FL 35.1%
NV 59.4%
OH 65.8%

Overall Winning Probability:
Kerry 76.9% Bush 23.3%

Bush -/+ Today (Yesterday)

-75.8 (-75.8) District of Columbia
-32.2 (-31.6) Massachusetts
-28.0 (-27.5) Rhode Island
-27.6 (-27.0) New York
-20.8 (-22.0) Connecticut
-18.9 (-20.1) Maryland
-18.7 (-17.7) New Jersey
-17.7 (-17.1) Delaware
-17.4 (-16.8) Vermont
-14.4 (-14.5) Illinois
-14.0 (-13.4) Hawaii
-13.7 (-13.1) California
-12.2 (-11.6) Maine
-8.5 (-7.9) Washington
-6.4 (-4.6) Michigan
-6.3 (-5.7) Pennsylvania
-5.4 (-4.4) Oregon
-4.6 (-4.2) Minnesota
-3.6 (-2.1) Wisconsin
-3.4 (-5.0) New Hampshire
-1.6 (0.0) New Mexico
-1.4 (-0.1) Iowa
-1.0 (-0.5) Florida
0.6 (3.7) Nevada
1.0 (0.8) Ohio
3.4 (4.1) Missouri
4.4 (5.0) Arizona
4.7 (5.2) Virginia
4.8 (5.1) Colorado
7.2 (7.0) Arkansas
7.9 (6.3) West Virginia
9.4 (17.2) Indiana
10.8 (11.4) Tennessee
10.8 (11.4) Louisiana
11.8 (12.4) North Carolina
12.6 (13.2) Georgia
14.2 (14.8) Mississippi
17.4 (18.0) South Carolina
17.8 (18.4) Alabama
18.1 (18.7) Kentucky
22.0 (22.6) Kansas
22.1 (22.7) Texas
22.5 (23.1) South Dakota
22.8 (23.3) Alaska
23.6 (24.2) Montana
24.0 (24.6) North Dakota
27.2 (27.8) Nebraska
27.9 (28.5) Oklahoma
36.0 (36.6) Idaho
37.1 (37.7) Wyoming
43.5 (43.8) Utah

Current Battleground Chart
Polimetrics Partisan Index
Polimetrics Partisan Index - Electoral Vote Analysis

The critical state of PA has moved steadily towards Kerry leaving Bush a ghost of chance there. The weird polling data has dropped out of the Zogby 4 day average of NM sending that state back to Kerry.

Spooky day with the National tracking polls - the one that most favored Kerry was Fox. Go figure.

The polls are now coming out at a rate of 60 per day. They don't show much change. If anything, the bin Laden tape actually hurt Bush's numbers, but I believe we are seeing more of the undecideds deciding for Kerry as expected.

I haven't written much about the senate, but appears the democrats would need a lot of luck to win. They need a net gain of one - and as I see it now, they will swap IL and GA, likely gains in AK and CO, likely loss in SC, and fight in OK, NC, SD. LA will probably go to a December runoff if the GOP doesn't win outright on 11/2.

The tossup senate races are in solid Bush states and three are current Dems. Even if they split 2-2, the GOP holds the senate.

Projection 10/30 5:00 PM
Kerry 60,192,000 49.8% 286 EV
Bush 58,836,000 48.6% 252 EV
Other 1,936,000 1.6%

click here for electoral map

Probability Bush wins each state:
FL 42.0%
IA 48.3%
NM 50.6%
OH 62.4%

Overall Winning Probability:
Kerry 73.8% Bush 26.2%

New Mexico is essentially a tie right now, Bush leads by about 1000 votes - right about where it was in 2000. If Gore had won NH in 2000, NM would have been litigated as well as Florida. Now, as it was then, NM is irrelevent unless WI comes back into play.

Colorado seems out of play as well - I never thought it was in play unless Kerry wins comfortably. Keep in mind in my projections, I only concern myself with scenarios that could actually change the outcome - last time only FL and NH were close enough to change the outcome. This time, it is FL or OH. Cheney must be working on his tan in Hawaii.

A year ago experts broke the battleground into three parts - the Southwest (NM, NV, CO, AZ) the Great Lakes (MI PA MN WI IA OH) and Florida (FL). I remember many telling me that the Southwest strategy was the best chance for the democrats. I simply replied with battleground probabilities showing the most important states in a close election. The top state is Florida - by far. 80% of the simulations in a tied election had Florida going with the winner. The six Great lake States came next. Kerry has intelligently focused most of his time doing the Midwest - Florida shuffle.

Three days to go and there is little movement in the polls. Yesterday, all the lazy media talked about was the effect the Osama Bin Laden video would have on the electorate. Does this qualify as an "October surprise?" I don't think so. Killing Bin Laden would have some effect on the election, but knowing that he is alive and hates America is not news. Frankly, all I care about the video is if it can be analyzed for any information to his whereabouts.

With all the early voting, the exit polls may be more suspect than the last election. In my county, 40% are voting absentee. Based on polling, the early voting has been about 50-50 between Kerry and Bush, and improvement for the Democrats from 2000 when Bush won the early voting by about 15%. Whether this is a portend for the election or just the democrats GOTV strategy of getting their voters to the polls early remains to be seen. I will say this: someone who has voted has a 100% chance of voting. Things happen on election day to prevent people from voting - work, life, patience get in the way. There is no down side in getting your supporters to vote early.

Projection 10/29 3:00 PM
Kerry 60,274,000 49.8% 291 EV
Bush 58,752,000 48.6% 247 EV
Other 1,936,000 1.6%

click here for electoral map

Probability Bush wins each state:
IA 38.9%
FL 45.5%
NM 48.0%
OH 51.2%

Overall Winning Probability:
Kerry 76.7% Bush 23.3%
Current Battleground Chart
Polimetrics Partisan Index

Very slight movement in polls today - this run is almost identical with 2 days ago.

One new piece of information was that are now approximately 143,000,000 registered voters, a staggering 5,000,000 more than my projection. Therefore I now predict the turnout will be over 120,000,000. I calculate 84% to 86% of the registered voters will vote - I derive this number by starting with last election's 83% and increasing it slightly due to interest and early voting.

Projection 10/28 5:00 PM
Kerry 58,718,000 50.1% 311 EV
Bush 56,561,000 48.3% 227 EV
Other 1,872,000 1.6%

click here for electoral map

Probability Bush wins each state:
NM 26.4%
IA 27.9%
FL 37.4%
OH 44.8%

Current Battleground Chart
Polimetrics Partisan Index

Some significant changes in the polls today - always subject to change.
Colorado has now passed Nevada and may be in play.
Wisconsin and Nevada both leave the battleground. It was a close call not taking WI out yesterday.
The four states in the battleground all now favor Kerry, albeit the two most critical are by razor thin margins.
Kerry's winning percentage has increased to over 80%.

Now one might ask how Kerry's winning percentage could be so high when both Ohio and Florida are so close. This is because Kerry only needs one while Bush needs them both. If these states were both 50-50, Kerry would have a 75% chance of getting at least one. Since they are both slightly Kerry, his winning percentage increases.

Also, removing WI from the battleground makes IA and NM unimportant - combined they can not replace the loss of OH for Bush. As of today, OH and FL are the only states that matter.

John Zogby said today that Kerry will win. I will not be so bold, but it is clear today why Zogby would say that.

Projection 10/27 8:30 PM
Kerry 58,623,000 50.0% 291 EV
Bush 56,653,000 48.4% 247 EV
Other 1,872,000 1.6%

click here for electoral map

Probability Bush wins each state:
WI 20.3%
IA 33.1%
NM 34.6%
FL 37.3%
OH 56.8%
NV 75.7%

Overall Winning Probability:
Kerry 76.7% Bush 23.3%


Today showed continued improvement for Kerry in the battleground while national numbers remained flat. PA, one of the original Big 3, now appears to be out of reach. Iowa has swung to Kerry. Additionally, WI has moved to more than +2 Kerry for the first time in weeks. NV now projects to a closer race than WI and is therefore moved to the current battleground along with WI, IA, NM, FL and OH. This leaves 64 possibilities where Kerry wins 43, Bush wins 20 and 3 ties which also count as a Bush win.

It also looks like the magic national popular number has returned to 0.6% that Kerry's votes must exceed Bush's to win Florida, the continuing middle state - the same percentage by which Gore won the populur vote in 2000.

A note about the incumbent rule whic says undecided usually break heavily to the challenger: This is almost always true when the challenger is less well known in the region being contested, which is clearly true of Kerry. An example where it may not hold is if the challenger was also a national figure. For example, Hillary Clinton would not benefit as much as Kerry from the incumbent rule. This rule also applies to state or local races - for example - I would not expect former Governor Knowles to benefit from the incumbent rule in the Alaskan senate race.

Projection 10/26 3:30 PM
Kerry 58,669,000 50.1% 284 EV
Bush 56,608,000 48.3% 254 EV
Other 1,872,000 1.6%

click here for electoral map

Probability Bush wins each state:
WI 31.5%
NM 38.5%
FL 38.6%
IA 51.5%
OH 55.6%

Overall Winning Probability:
Kerry 72.6% Bush 27.4%

Latest run, check out the current battleground chart and compare it to the "Polimetrics Partisan Index I ran last in April. Only Ohio is a suprise among the critical states. I have conjectured that projected outcome can be explained more by the demographic and cultural make-up of a state than by early polls. These final polls are looking much more like the partisan index.

Kerry's numbers improved slightly, but all movement is within the margins of error for various polling agencies. It really comes down to get-out-the-vote.

REVISED Projection 10/25 11:30 PM

Kerry 58,456,000 49.9% 284 EV
Bush 56,830,000 48.5% 254 EV
Other 1,872,000 1.6%

Probability of Bush Winning:

NM 33.6%
WI 36.4%
FL 41.3%
IA 58.2%
OH 67.5%

Overall Winning Probability:

Kerry 65.8% Bush 34.2%

Ok, the earlier results are modified due to a revision in the Gallup numbers and an addition of the LA Times poll. I also added individual probabilities for the 5 critical states and an overall probability of winning based on independence among the results from these 5 states. This may be an invalid assumption because there is almost certainly a correlation among the expected results for WI and IA and possibly OH.

These results are more in line with prior runs. One can see how even the smallest outlier can really swing the numbers. Anyone who says they can predict a winner today must be looking at numbers not reported to the public.

If you want to really get educated about polling check out the articles by The Mystery Pollster . This series of daily articles from an experienced pollster really gets behind the calculation of the numbers and discusses the recent controverisies.

Projection 10/25 4:30 PM

Kerry 58,087,000 49.6% 257 EV
Bush 57,192,000 48.8% 281 EV
Other 1,872,000 1.6%

I might as well call this run of the model "Election 2000". Kerry wins the popular vote, Bush wins the Electoral vote and Florida ends up at 0.1, right in the middle.

A couple of things about today's run: it includes the latest Gallup poll which has been highly critcized due to its sampling of republicans in much higher percentages than the 2000 exit polls. I don't judge Gallup here - I include them as I would any other pollster. Without Gallup's poll, the results would be similar to yesterday's run.

Current discussion is that the five states that will decide the election are NM WI FL IA OH. Other states may be in play but for a candidate to win them means they have probably already won the election. For example, Kerry may win Nevada, or Bush may win Minnesota, but if that happens, the middle states have probably already gone to the winner.

There are 32 possible outcomes for these 5 states: Kerry wins 20 of them, Bush wins 10 and there are 2 ties which also means Bush wins. (Bush needs 42 Evotes, Kerry needs 28 Evotes from these 5 states).

Current Probabilities of victory based on a 2.5% Standard Deviation for the partisan Index:
Kerry 51.5% Bush 48.5%

Very Close Indeed

Projection 10/24 3:30 PM

Kerry 58,600,000 50.0% 284 EV
Bush 56,677,000 48.4% 254 EV
Other 1,872,000 1.6%

Not much change from yesterday - the new polls look better for Kerry only because the undecideds have decreased and are moving heavily towards Kerry, as expected.

Hawaii has had a couple of strange polls that look more like a battleground poll. This state has always been rated solid Kerry - the partisan index rating is +23 Kerry, so I don't put much faith in these polls. However, Hawaii has now dropped behind California in my ranking, still safe Kerry.

This leads me to a discussion of variability in the partisan index. When testing this model on the 2000 election, there was one state that fell outside the margin of error on projection from the 1980-1996 election data and demographic factors: West Virginia moved eight percent away from the expected partisan index in 2000. Now you might say this discredits the model, but the reality is one would expect 1 in 20 states to fall outside a 95% confidence interval, about two standard deviations from the mean. West Virginia was not only the only state outside of the margin of error, but actually moved outside a 99% margin of error, nearly 3 standard deviations from the mean.

What will the surprise state be this year?

Projection 10/23 10:00 PM

Kerry 58,366,000 49.8% 284 EV
Bush 56,913,000 48.6% 254 EV
Other 1,872,000 1.6%

Florida returns to the middle state, but all results are well within the margin of error. Today the battleground is reduced to FL, OH, WI and IA.

The news today was Bush focusing the remainder of his campaign on WI, IA, FL, and NM. He either must feel safe with OH or is writing it off. Seems strange based on these stats, but he may be viewing the strategy of winning WI, IA and FL which is a 271-267 win or even NM instead of IA for a 269-269 tie. The actual polls have Kerry in the lead in OH, it's only the elasticity of the partisan index that puts Ohio just below Florida in my model.

Unlike Florida, losing Ohio doesn't leave Bush hopeless. Still, I find it hard to believe Bush can lose Ohio without also losing Wisconsin.

Early voting statistics in Iowa are about 2-1 in favor of registered Democrats. Will the democratic strategy of getting people to early vote succeed? It will be interesting to measure this effect after the election.

Projection 10/22 10:00 PM

Kerry 58,929,000 50.3% 304 EV
Bush 56,352,000 48.1% 234 EV
Other 1,872,000 1.6%

Most states are behaving consistant with the partisan index - most notably the continued reddening of Iowa. The one major surprise has been Ohio which is now ranked on the blue side of center. There have been many polls this week rangiong from +6 Kerry to +2 Bush, but no poll has Bush over 47%, a definite sign of trouble for an incumbent. The movement of Ohio now makes Wisconsin the key state - Bush would need to swing 1.7% to win WI and FL to pull off a 271-267 victory. Note the Popular vote difference in 2.2%, so Bush could again win the election and lose the vote.

Projection 10/21 7:00 PM

Kerry 58,983,000 50.3% 304 EV
Bush 56,288,000 48.1% 234 EV
Other 1,872,000 1.6%

Main difference today is Iowa and Ohio switching. Good polling in OH and FL for Kerry today. Two good polls for Bush in IA.

Today Gallup had Kerry +6 in Ohio and -7 in Wisconsin! Does that make any sense? WI is 2-3% more Dem by the partisan index, so Gallup's results would be a net deviation of 16% from expectation!

Projection 10/20 7:15 PM

Kerry 59,193,000 50.5% 291 EV
Bush 56,087,000 47.9% 247 EV
Other 1,872,000 1.6%

A small improvement for Kerry based on national polls and some new state polls. Ohio calculates to a difference of about 8,000 votes out of 5.1 million to be cast!

Although the national polls bounce around due to sampling error and methodology, internals of polls have been remarkably consistent: Republicans are about 90-9-1 for Bush, Democrats are about 89-10-1 for Kerry and Independents are about 50-45-5 for Kerry. Deviations in the polls are often due to likely voter screens and the demographics of the sampled group. It seems logical to weight by party ID which is so highly correlatated to the vote, but some pollsters argue that party ID is self-selected and changes with the mood of the voter. We will have to wait for the vote to measure the wisdom of these pollsters.

Projection 10/19 4PM PDT.....

Kerry 59,001,000 50.4% 291 EV
Bush 56,470,000 48.2% 247 EV
Other 1,689,000 1.4%

After months of waiting, I have published the first battleground projection - better late than never! The poll shows a near dead heat (big suprise) - with Kerry up by 0.6% in Florida, the current decisive state.

What makes this projection different than the hundreds of projections already out there, many of which I have linked?

1. The projection uses a partisan index - a best estimate correlation among the states based on past elections and demographic projections by the US Census Bureau. For example, midwestern states such as Iowa continue to trend towards the right while states like Arizona have trended left due to internal migration. Using multiple regression on variables such as ethnicity trends, population growth, regional factors, etc, I determine a partisan index - what many call blueness and redness. Final results have been adjusted for the candidate's home region based on past elections since 1980.

2. The projection takes into account national polls, for adjusting the partisan index to current status and state polls to adjust the partisan index within its determimed 95% confidence band (about 3-5% based on past performance.) In other words, because the methodology for state polling is not consistant, I use a Baysian approach in adjusting all state results by the partisan index. For example, in this run the most extreme adjustment was South Dakota which has an adjusted partisan index of about 28% but has reported a state poll with a 10% difference. The actual result of +18.6 is a more reasonable estimate than the reported poll. Note, these adjustments are automatic based on model parameters - not based on any subjective analysis.

3. Undecided voters are assumed to break in accordance with past elections when one of the candidates is an incumbent. Third party voters are determined based on an expected national vote of about 1.5% adjusted by each state's third party relative voting trends since 1980.

4. Using US census data, I have also projected total votes for each state to determine a predicted national share.

Why I am I doing this?

I am a Math/Statistics professor who has always been interested in the study of political statistics. This is my latest attempt at making an empirical tool to predict and study presidential elections. I hope to do for politics what Bill James has done for baseball - to educate people, expose misconceptions and ignorance, cut through the rhetoric, and to examine politics using purely statistical methods. Most of all, I want to have fun with this - politics is the most entertaining game in town.

For the record, I am not unbiased - who is today? I have already cast my ballot for the challenger in this election. My rhetoric, (probably like yours), is posted all over the Internet at places like Daily Kos. I will keep this place rhetoric free - notice there are many good data links from "the other side" - like "Election Projection", one of my favorites.

When it comes creating political numeracy, I hope we are all on the same side.

Mo