In a wide-ranging discussion, a number of participants urged Romney to refrain from attacking rival Rick Santorum with the scorched-earth intensity that he directed at Newt Gingrich.

◼ Conservatives urge Romney not to attack Santorum - Byron York/Washington Examiner

Romney told the group he had thought Gingrich's surge would be the last challenge in the primary campaign, only to see Santorum surge with victories in Minnesota, Colorado, and Missouri last Tuesday. Now, with Santorum the man of the moment, Romney joked that it is time to get the oppo research up and running again. He quickly added: No, no, I'm only kidding.

But Romney's remarks suggested he wasn't entirely kidding. "He said Rick has to be held up to the same scrutiny as everyone else," says one meeting participant.