Does Obama Really Have a Double-Digit Lead?

It's one of the golden rules of politics: praise the polls that show your candidate in good shape--and dismiss the ones that don't.

So it's no surprise that Team McCain is now trashing a pair of brand-new surveys--from the Los Angeles Times/Bloomberg and this magazine, incidentally--that show Barack Obama ahead by 15 points. "It is important that both the campaign, as well as reporters covering the campaign, not overreact to every single survey that is released," the Arizona's pollsters write in a memo. Given that there are three or four such surveys released every week--none of which can predict what will happen on Election Day--they're undoubtedly right. Too much overreacting is bad for one's joints. But that doesn't change the question: is Obama currently clobbering McCain by double digits--or have some loopy pinko pollsters have simply led us astray?

The answer: it depends. The major difference between the Newsweek and Los Angeles Times polls and some other recent surveys--which typically show Obama ahead by about five points--is party identification. In the NEWSWEEK poll, 38 percent of the 896 randomly-selected respondents were Democrats, 23 percent were Republicans and 35 percent were Independents, while the Los Angeles Times polled a 1,115-person pool that was 39 percent Democrat, 22 percent Republican and 27 percent Independent (with about 10 percent answering "other," an option not offered by NEWSWEEK). According to Team McCain, these 15-17 percent gaps in party ID are "out of line with what most other public polls are showing"--and that imbalance, they say, inflates Obama's actual lead by about eight points. Voila. No double digits.

The problem here is that unlike race, age and gender, party ID is fluid--and even extreme swings might reflect actual changes in the mood of the electorate. "This is a canard," says NEWSWEEK polling maestro Larry Hugick when asked about the McCain memo. "Both parties do it. But ID isn't a fixed property. In fact, it's associated with the candidates. It's been proven that as a candidate goes up in the polls, so does his party. Same when a candidate goes down." What's more, recent surveys have shown that a double-digit gap in party ID doesn't necessarily result in a double-digit lead. The June 3 CBS pool, for example, was 38 percent Democrat and 24 percent Republican--a 14-point gap--but Obama led by only six. A week later, a similar AP/Ipsos sample group (37 percent Dem and 23 percent Republican) produced a similar result (Obama by seven). So to blame Obama's big leads solely on fluky party ID--instead of, say, his own appeal to voters--is somewhat self-serving, and impossible to prove.

Of course, Team McCain is more concerned with psychology than mathematics. As the Politico puts it, they're "trying to ease anxieties and calm fears among party elites and activists that Obama is developing a lead so significant that it can't be overcome." But even McCain's keepers admit that if the L.A. Times party identification gap is "recalculated" to "ten (29% GOP / 39% Dem), the ballot would be 40% McCain – 47% Obama." That's a more conservative--and, according to the RealClear Politics 6.9-percent polling average, a more consensus--estimate of Obama's lead. But it's still still seven points--which, according to the sophisticated projection engine over at FiveThirtyEight.com, would be enough to propel Obama to a 344-194 electoral college win on Nov. 4.

Given that, the best answer to "Does Obama Really Have a Double-Digit Lead?" is probably another question:

"Does it really matter?"

UPDATE, June 26: For more, check out the latest column by Pollster.com's Mark Blumenthal. An excerpt:

The memo lists party identification results in 10 polls from May and June that average out to 38 percent Democrat and 29 percent Republican. LAT/Bloomberg had roughly the same proportion of Democrats (39 percent) but far fewer Republicans (22 percent).

The problem with that comparison is that four of the most recent polls -- by Newsweek, AP/Ipsos, ABC News/Washington Post and NBC News/Wall Street Journal -- all reported a Republican identification in the range of 23 percent to 24 percent and Democratic ID ranging from 33 percent to 37 percent. While the Democratic advantage on the LAT/Bloomberg poll is bigger, it is not wildly different.