House Budget Chairman U.S. Rep. Paul Ryan (R-WI) and his widow’s peak in D.C. last month. (Win McNamee/Getty Images)

With the GOP veepstakes heating up, many eyes are turning to Rep. Paul Ryan, who gave a big boost to Mitt Romney in his home state of Wisconsin this week. No wonder: The youthful House Budget Committee chairman has a strong conservative fan base, a great rapport with the frontrunner — and a potential game-changer of a widow’s peak.

You’ve noticed it even if you think you haven’t. That furry little dip in the center of his hairline, like the notch at the top of a valentine. You see it now? Yeah — how about that!

Colin Farrell: Nice widow’s peak. (AP)

Ronald Reagan in 1975. (Associated Press)

Research suggests widow’s peaks are a plus at the polls. Shawn Rosenberg, a professor of political science and psychology at the University of California-Irvine, did a study in the late 1980s that found subjects were drawn to photos of mock politicians with certain facial characteristics. Widow’s peaks, though more so on female candidates, were “a clear positive,” he said. “It was associated with being seen as more competent and with greater integrity.” (Really, why? “To be frank, I have no idea,” he told us.)

Andrew Jackson on the $20 bill. (Dan Loh/AP)

Rosenberg said Ryan has other features that subliminally play well with voters: Rounded upper eyelids and thin lips. But looking as young as Ryan does could actually hurt, the study found, while square jaws surprisingly have no sway on voters.

Ryan’s office declined to comment on the congressman’s hairline, but he’s definitely aware of it. “When I look in the mirror, I see a broken nose and a widow’s peak,” he joked to a forum at Marquette University law school last year. “I don’t see a future president.”

Paul Ryan on Capitol Hill in February. (Carolyn Kaster/AP)