Romney brings knowledge of economic issues, the Utah senator said Thursday, he has been fully vetted by the primary process and "if you're afraid McCain is going to drop dead, he's got a vice president who is fully up to speed and can step in."

"It makes sense to put the two of them together."

McCain can focus on his foreign-policy experience and reputation, and Romney can say, 'I'll help you out with domestic policy,' '' Bennett said.

He added there has been some talk of Texas Sen. Kay Bailey Hutchison being named instead of Romney.

"I'm guessing [McCain's advisers] think, 'Well, maybe we need a woman - she might attract the women who are disappointed that Hillary [Clinton] didn't win to come over to the Republican Party,' " Bennett said. "But I think women who feel that strongly about Hillary aren't inclined to vote Republican."

Gov. Jon Huntsman Jr., a longtime McCain backer, says he has no insider insights into the Arizona senator's decision, calling it a "personal decision" for the presumptive GOP nominee.

"It's one where chemistry will really matter in the end, the ability to get along," Huntsman said. "[McCain] has been very outspoken that the primary ability will be the ability to assume the presidency should something happen to McCain."

Regardless of the choice, and of who wins the White House in November, Bennett is convinced the Senate will lose some of its 49 Republican seats to Democrats. But he doesn't think they'll fall below the 40 needed to sustain a filibuster.

"We will retain enough seats to remain relevant."

smcfarland@sltrib.com