With less than a week before showtime, the polls are already jam packed. But the real stars of the eleventh hour are the undecided voters, who still (incredibly, miraculously) haven’t made up their minds. And apparently they’re more numerous than one might think, with one in seven voters saying they might go either way, according to a recent poll.

But are these vacillating voters really still deciding? Or could their minds have already formulated a choice, without their even realizing it? University of Virginia psychologist Brian Nosek suspects the latter is true, and has partnered with colleagues at Harvard and the University of Washington to test whether humans form mental associations that differ from what their conscious recognizes.

To do this, the researchers used the Implicit Association Test, which has been up and running for a decade now and has logged around 7 million responses. Since the 2008 presidential race began, the team has tested more than 25,000 voters on their implicit preferences concerning the two candidates. Of that group, around 4,000 (15 percent) declared themselves undecided. But the test results for a significant number of these so-called undecideds showed a clear implicit preference for Obama or McCain. Here’s how the team summarized their results:

• Implicitly, Democrats are strongly pro-Obama, and Republicans are strongly pro-McCain, similar to their explicit preferences.
• Independents are implicitly pro-Obama, on average, similar to current polling results.
• The most intriguing subsample is the large number of undecideds who appear to be leaning toward McCain implicitly and toward Obama explicitly.

The last finding, of course, being the elephant in the room (or the polling booth).