Thursday, July 17, 2008

Likely Voters More Republican?

In the ABC/Washington Post poll that showed Obama leading 50-42 among registered voters, the “likely voter” screen they used showed Obama only leading 49-46. When a pollster uses a “likely voter” screen they are applying their own special secret sauce formula to determine who is likeliest to vote.

The critical element that skews likely voters more Republican this time is that likely voters = engaged voters, engaged voters skew older, and older voters skew McCain in this race.

Marc Ambinder explains:

Based on data, studies and experience, pollsters assume that older voters tend to reach information saturation earliest, tune in the earliest, and pick their candidates the earliest. Likely voter models this far out don't oversample older voters per se -- they oversample voters who have made up their mind and aren't likely, even if they say they're likely, to change their minds. John McCain's leading among older voters, but not by much. So when younger voters -- younger than 65 -- begin to make up their minds in the fall, likely voter models will move back into equilibrium and Obama's lead among registered voters should begin to match his lead among likely voters.
Chuck Todd-led First Read agrees:
[R]ight now, pollsters will tell you that with older voters leaning McCain these days, any likely voter model is going to favor McCain for now. If Obama moves younger voters as well as many observers assume come October, the likely voter numbers could change.
However, a key assumption needs to be called into question. This year, are the engaged voters skewing older? Are older voters reaching information saturation the earliest? Pew finds a surprise for pollster likely voter assumptions:
Compared with previous election cycles, voter engagement is up among all demographic groups, but has increased more among voters under age 50 than among older voters. Uncharacteristically, the youngest voters -- those under age 30 -- are at least as knowledgeable, and in some cases more knowledgeable, about candidates' positions on Iraq and abortion than are older voters.
The assumption reported by Ambinder and Todd is that younger voters will be making up their minds closer to the election and that this will change the likely voter screen at that time. In other words, the pollsters are correct now (but not predictive of November) and they will also be correct in October (and predictive of November) when they expand their likely voter screen. All we are waiting on is the young voters to tune in and make up their minds (presumably skewing things back toward Obama).

This predicted dynamic flies in the face of the evidence. Pew reports two unprecedented findings in their poll. First, Democrats are expressing stronger interest in the campaign than Republicans for the first time since Pew began tracking in 1992. Second, the percent of voters more interested in the campaign relative to four years ago (usually hovering near 50% across the board) shows a huge jump on the Democratic side to 71%.



If engagement and interest is what makes a voter a likely voter, and if younger voters have reached saturation ahead of older voters reflected in their superior grasp of information, then any likely voter screen that doesn't currently skew Democratic is probably an incorrect likely voter screen.

60 comments

Edmund in Tokyo said...

Is there any information out there about how the various pollsters are deciding who is likely to vote? Without this it's going to be virtually impossible to make sense of the various polls...

Michael said...

any likely voter screen that doesn't currently skew Democratic is probably an incorrect likely voter screen.



And what is the implication of that for the current polling? Does it favor Obama or McCain?

Anonymous said...

"Is there any information out there about how the various pollsters are deciding who is likely to vote?"

Don't they simply ask the person if they're likely to vote in November?

Sean said...

Edmund - unless a polling group specifically discusses its methodology, it's mostly inferential. If Obama's lead is 8 with registered voters but 3 in likely voters, it's easy to infer that the likely voter screen skews toward McCain (i.e, that McCain's voters are more engaged, more info saturated, etc.). You'd have to check on a poll by poll basis.

Michael - all it means is when you read in a poll that Obama is further ahead among registered voters than likely voters, be very very skeptical of the conclusions that pollster has made about likely voters. As Pew finds, the age group and partisan breakdown of how people are engaged this time are dramatically different than past patterns. Pollsters are using old assumptions about older voters being more engaged that don't appear to hold water this time around.

such sweet thunder said...

Sean, to correct your last line:

Pollsters are using old assumptions about older voters being more engaged that don't appear likely to hold water this time around.

I'm as big an Obama supporter as any. But we still need to make this happen. Until election day hits, and the models are proven wrong, they are still illustrate an historical trend. Which, on the whole, is more likely to be closer to the truth than further away. To some extent, we have to change the trend before we can declare it dead.

Anonymous said...

Gee, I wonder why you didn't use the data from the ABC poll with the likely voter model? Or even provide a link to it? Wouldn't that make more sense? Of course it does, but it doesn't support your theory.

http://abcnews.go.com/images/PollingUnit/1066a308Politics.pdf

Take a look at page 2. There's a huge drop the level of young people and Democrats who say they are certain to vote in November. Not so for the elderly and Republicans.

46% of people ages 18-29 say they are certain to vote in November versus 73% of people over 65.

This isn't the first time you've done something like this.

Sean said...

Anon - impugn me personally if you want, but go back and re-read this (from Ambinder):

"Based on data, studies and experience, pollsters assume that older voters tend to reach information saturation earliest, tune in the earliest, and pick their candidates the earliest. Likely voter models this far out don't oversample older voters per se -- they oversample voters who have made up their mind."

The point of the post is showing how this year the makeup of the most engaged and informed part of the electorate does not resemble past patterns. In past years, the likely voter screens would have been in line with consistent data. Not this year.

This year, it is inarguable that Ds are paying more attention than Rs (unprecedented). Obama's hard support is 70-100% more than McCain's hard support. If info saturation relates to engagement and knowledge of the issues, younger voters are outpacing older voters.

If ABC/WaPo is NOT using the methodology Ambinder and Todd report that pollsters use in their likely voter screens, so be it. If my analysis is wrong, then it has to also be true that NBC's political director doesn't understand how pollsters put together polls. Is that more fun or less fun as a conclusion than that my work is bad faith?

michael said...

Sean, Different Michael here. I think the latest personal attack by yet another "brave" anonymous simply points out what many of us have been saying for weeks. At the bare minimum, anonymous posters should not be allowed on this site. 98% of the trollers and venom-spreaders are anonymous. Esp. when we know trollers are getting trolling points from the McCain website for spamming various blogs.

You posted a highly rational, interesting and intriguing technique on likely voter models, and the anon troll's response was to slander you. It gets old and really detracts from this site, which is a quality one.

Edmund in Tokyo said...

Thanks for posting the link, anonymous (1:30 AM). And it does look like in this case they're assigning likelihood to vote simply by asking people. (Although it doesn't specifically say that.)

Possible reasons for the drop in younger people planning to vote since March:
a) Less interest in the race among Democrats (who skew young) now that the primary is over and there's nothing exciting going on.
b) Obama perceived to have moved to the center / flip-flopped / not be the change people thought, which is de-enthusing younger voters.
c) Just sampling error in the sub-samples.

If it's (a) and/or (b), presumably it should be possible to reenthuse them around election time when there will be more going on and a stronger contrast with McCain, especially if it looks like a close race. But like Such Sweet Thunder said, that's not a foregone conclusion.

John said...

I don't think Anonymous is right.

The ABC/WaPo poll shows 75% of Obama supporters saying that they will definitely for him, and 9% saying that there is a good chance they will vote. For McCain supporters, it has 68% saying that they will definitely vote and 14% saying there is a good chance.

I don't see how that can possible cause Obama's numbers to drop by 9 points from a 12 point lead among all respondents to only a 3 point lead among likely voters.

It seems that they are using additional criteria to determine likely voters (as Sean suggested).

Anonymous said...

Sean you're analysis is off. According to what Nate has just posted the likely voter models don't skew far enough towards McCain. This means that McCain's advantage is UNDERSTATED in the polls, both registered and likely because it is the dems and young people who are engaged and its the republican voters who have yet to make up their mind and are listed as "undecided" on most polls.

John said...

I made a mistake in my above post.

The "good chance" refers to the chance they will change their mind rather than the chance that they will vote.

However, the "definitely vote" numbers are clearly not the only criteria that ABC/WaPo are using to determine likely voters.

Edmund in Tokyo said...

john, I don't think the numbers you're quoting are certainty to vote numbers. They're answers to this question:

3b. (IF NAMED CANDIDATE) Would you definitely vote for (CANDIDATE), or is there a chance you could change your mind and vote for someone else?

That confirms the picture we've been seeing elsewhere that McCain's support is softer than Obama's, but it doesn't tell us whether Obama's many supporters will actually get off their bums and vote.

I couldn't see the certainty to vote numbers by preferred candidate - if they're there that should confirm whether their screen is just based on asking people or not - but it does say that: "resolve to vote has gone from 82 percent to 66 percent among Democrats" which seems consistent with McCain having a big advantage on people who said they'd vote.

John said...

Edmund, you are right, they are using "definitely vote" differently in the two cases. My mistake.

asmodeus said...

Hey, take it easy Sean! You wrote a great post, take confidence in it and ignore those anonymous ignorami who don't have the wit to even think up a name for themselves.