George Packer compares the Republicans in 2012 to the Democrats in 1972:

McGovern’s debacle forced the Democratic Party to find its way back from the ideological wilderness—from being the party of delegate quotas and “acid, amnesty, and abortion.” Every successful Democrat after 1972, from Carter to Clinton to Obama, has had at least one foot in the party’s center. A Gingrich rout in November might have the same effect on Republicans—it might drive their party back toward the center, and toward mental health, in 2016. But if Romney wins the nomination and loses the election, the party will continue down into the same dark hole where Palin, Bachmann, Perry, Cain, Santorum, and now Gingrich all lurk. So a sane Republican has a terrible dilemma, today in Florida and beyond. That’s what happens when political parties are captured by a minority of fervent believers.