“The G.O. P. has to make a stand,” said Scott Reed, manager of the 1996 presidential campaign of Bob Dole. “This is what the base and social conservatives really care about, and we need to brand her a liberal with some out-of-the-mainstream positions. Forget about cosmetics and ethnic heritage, and focus on her record.”

“If Republicans make a big deal of opposing Sotomayor, we will be hurling ourselves off a cliff,” said Mark McKinnon, a senior adviser to Mr. Bush and a long-time advocate of expanding the party’s appeal. “Death will not be assured. But major injury will be.”