Shift in national popular polls favors Obama

President Barack Obama is now leading in polls against each of the individual Republican opponents he may face on Election Day. And for the first time in months, Obama is leading against a "generic Republican" opponent. It's true that polls conducted 350 days before an election have very little predictive power--but they are a meaningful indicator of the public mood as the primary season lurches into gear.

The chart below shows the percentage of poll respondents who say they'd vote for Obama against each potential opponent in a head-to-head match up. I created the data using Real Clear Politics' aggregated trends research. On average, more than 90 percent of the respondents select one of the two candidates; others decline the choice, or say they're undecided.

Obama is leading in the equivalent of a landslide against Newt Gingrich (54.6 percent) and Herman Cain (55.1 percent). He also performs well against two other Republican challengers not shown on the chart: Rick Perry (55.0 percent), Michele Bachman (58.1 percent), Jon Huntsman (55.3 percent) and Ron Paul (53.3 percent). For comparison, in 2008 Obama won with 53.8 percent of the votes that went to either Obama or John McCain--a margin strong enough for a convincing win in the only presidential tally that matters: the breakdown of votes in the Electoral College.

The picture changes, however, when Obama is matched up against the present consensus Republican frontrunner, former Massachusetts Gov. Mitt Romney. In a head-to-head matchup against Romney, Obama has a narrow majority of 50.8 percent support in this data set. Obama's margin over Romney has narrowed a little in the last few days, but it has held steady over the last few months. These trends are worth following closely, since amid all the other turmoil in the GOP field, Romney has remained the chief front-runner in both the polls, narrowly--and in the prediction markets, convincingly.

The most striking finding in this set of poll numbers is that Obama is finally leading versus the "generic Republican," who has been beating him soundly over the last few months. Here, too, the president's edge is narrow, at 50.5 percent--but it is a significant shift nonetheless. A "generic" candidate is always a more effective candidate than any specific candidate, since individual candidates are better-known quantities, for better and (usually) for worse. When polled on their support for generic candidates, respondents can project the most electable or ideal candidate, regardless of whether those qualities actually exist among the field of candidates in play. That's why specific candidates almost always poll worse against "generic" candidates.

These trends are taking place in spite of what's called the anti-incumbent bias, a trend in public sentiment that typically depresses incumbent poll numbers compared to the final Election Day outcome. In the same way that a specific candidate fares worse than a hypothetical one, a known incumbent--particularly a sitting president--tends to poll lower than an unknown or lesser-known opponent will. As Election Day draws closer, incumbents tend to gain ground in the polls, benefitting from the inevitable closure of the knowledge gap that can make opposition candidates attractive over the balance of an election cycle.

The trend now evident in the polling numbers is that the "generic Republican" has converged toward Romney. As the electorate comes to think of this specific candidate as the eventual nominee, the beau ideal of the "generic Republican" loses a good deal of its generic appeal.

However, while Obama may have enjoyed a good recent run in opinion polling, the prediction markets haven't grown noticeably more bullish on his re-election prospects. The data from the leading such markets, such as Betfair and Intrade, show Obama with a 51.6 percent likelihood of reelection. That prediction assumes Obama has a 68.3 percent likelihood of facing Romney--who would likely give the incumbent a tight re-election fight--and a 31.7 percent likelihood of facing someone other than Romney. Still, once prediction market traders consider the anti-incumbent bias--something all polls watchers should do--the poll results become stronger for Obama. Traders are likely factoring in economic concerns in hedging their Obama bets--but several trends in recent economic data could brighten Obama's prospects soon.

And always remember that you can continue to follow the likelihood of both the Republican nominee and the winner of the general election along with the Signal in real-time.

David Rothschild is an economist at Yahoo! Research. He has a Ph.D. in applied economics from the Wharton School of Business at the University of Pennsylvania. His dissertation is in creating aggregated forecasts from individual-level information. Follow him on Twitter @DavMicRot and email him at thesignal@yahoo-inc.com.

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