McKenna said Romney, who bought and reorganized companies when he led Bain Capital, talks of "closing the deal," and seems to approach the campaign like a corporate takeover in which GOP delegates are "shareholders."
"In takeovers, you don't care about burning the other guy down because you're never going to see him again," McKenna said. He said Romney seems unaware that "he'll need guys like Gingrich and Santorum not to hate his guts."
Some Republicans say the campaign quarrels are no worse than those between Obama and Hillary Rodham Clinton, which lasted deep into the summer of 2008. McKenna disagrees.
With Obama and Clinton, he said, "it was personal, but just around the edges. This is personal to the core."
Santorum and Gingrich have sizeable egos and ambitions, so it's possible they would be fighting just as hard against Romney if the ads against them had been milder. Whatever the case, both men seem to take pleasure in highlighting Romney's weaknesses, even though it might hurt their party in the fall against Obama.
Gingrich, who's refused to bow out despite losing crucial races this past Tuesday in Mississippi and Alabama, derided Romney's third-place finishes.
"If you're the front-runner and you keep coming in third, you're not much of a front-runner," he told supporters after falling short in the South.
Gingrich faces massive odds. But his speech at least gave him a measure of payback for the withering TV ads that sent him reeling in Iowa, and again in Florida.
Copyright 2012 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.