Marco Rubio and an aging party in search of a spark

“The identity politics people in the party want a champion who looks like him to mitigate accusations of racism,” said Ben Domenech, a conservative writer. “And the classical conservatives look at him and say, ‘This is somebody who can sell our ideas to the public.’ ”

Conservatives have long had a philosophical contempt for politics driven by gender, racial or class designations. But those sentiments are giving way as the party tries to compete with Democrats, who galvanized support among targeted demographics to decisively win consecutive presidential elections.

Republican voters are overwhelmingly white: The composition of the electorate in almost every contested state during the 2012 party primary was about 90 percent or more non-Hispanic white, according to exit polls.

A New York Times/CBS Poll this week found that 68 percent of Republicans think America is ready to elect a Hispanic president. And after nearly eight years in which Republicans have angrily disputed charges that their opposition to President Obama is rooted in racial animus, Mr. Rubio could serve as an unspoken, but forceful, rebuttal.