The former Pennsylvania senator has always lagged among female voters, and President Obama would happily exploit that in the general election.
Much of what's been written about Rick Santorum's political history has centered on 2006, the year he suffered an 18-point landslide loss to Democrat Bob Casey in an otherwise awful year for Republicans.
But the more instructive campaign to look at to assess Santorum's electability is his 2000 victory against then-Democratic Rep. Ron Klink, an election he won with 52 percent of the vote. What's striking about the exit polling from that race is the huge gender gap Santorum engendered even in victory.
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Against a Democratic congressman who opposed abortion, Santorum dramatically underperformed with women voters. That would likely repeat itself if he emerged as the Republican nominee against President Obama.
Santorum won an impressive 57 percent of the vote among men; that number increased to 60 percent just looking at white men. But among women, Santorum lost to Klink, winning just 48 percent of the vote. Among white women, he barely inched past the Democrat, 52 to 47 percent.
Klink carried working women, 53 to 45 percent, but among women who stayed at home, Santorum comfortably prevailed, 56 to 42 percent.
Since that election, Santorum wrote his book It Takes A Family and has been even more outspoken on cultural issues that galvanize the GOP base and some culturally conservative independents, but have been a turnoff to many female voters. In 2006, Casey won a whopping 61 percent of the female vote, as part of his across-the-board win.
Santorum's approval numbers nationally are artificially high right now, since he's a blank slate to many Americans and has largely avoided the relentless attacks that Romney unleashed against Newt Gingrich. But that's bound to change. And if Santorum emerged as the nominee against Obama, the president's re-election team would have a boatload of oppo to use against him, aimed at making him unacceptable to many female voters.
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