Successful presidential nominees often have helped redefine their parties. Ronald Reagan’s conservatism changed the Republican Party when he became its nominee in 1980. Bill Clinton portrayed himself as a New Democrat, which proved a key to his victory in 1992. In his 2000 campaign, George W. Bush used the term “compassionate conservative” to put distance between himself and the congressional wing of his party that had been defined by Newt Gingrich.

In this campaign, the opposite seems to be the case. “This year, it seems to me, the party is the sun and the candidates are the planets. . . . They are trying to prove to primary voters that they are reliable and trustworthy when it comes to the basic platform of the GOP,” said Pete Wehner, a Republican strategist and former Bush administration adviser…

A Republican strategist, who spoke on the condition of anonymity to talk candidly about the election, agreed.

“What Obama needs to do now is force the Republican nominee into supporting the tea party wing of the party over the next nine months,” he said. “Can you tie the nominee to the congressional Republicans? If he can do that, now you’re talking about a real problem.”