WASHINGTON — Remember Ronald Reagan's famed 11th commandment, do not speak ill of fellow Republicans? It looks as if this year's presidential candidates have forgotten it.
At Wednesday's CNN/YouTube debate, former New York Mayor Rudy Giuliani accused former Massachusetts Gov. Mitt Romney of running a "sanctuary mansion" because Romney had illegal immigrants doing yard work at his home. Earlier in the week, Giuliani's campaign manager called Romney a "mediocre one-term governor."
Romney has lambasted Giuliani's judgment in hiring as police commissioner Bernie Kerik, who was indicted on corruption charges recently. Both candidates routinely accuse each other of resembling Hillary Clinton, perhaps the unkindest cut of all among Republicans.
To be sure, there have always been occasional edgy skirmishes in Republican primary campaigns: "Stop lying about my record," Kansas Sen. Bob Dole snarled to George H.W. Bush in 1988. A vicious whispering campaign against Arizona Sen. John McCain in South Carolina in 2000 suggested that McCain was crazy and the father of an illegitimate black child. (The author of that campaign was never identified, but it helped save George W. Bush's candidacy.)
But rarely has the level of personal nastiness among Republican contenders — beyond simple policy disagreements — risen so early and so systemically, and been conducted so openly by the candidates themselves and their campaigns.
``Clearly, the candidates are beginning to more directly attack each other," said Peverill Squire, a political scientist at the University of Iowa. "Certainly between Giuliani and Romney it's getting personal. They're taking it to a whole other level."
Their campaigns insist that they'd like to keep it positive and that it's the other guy who's to blame.
Romney spokesman Kevin Madden decried "Mayor Giuliani's nasty side," saying "the mayor's tone has turned ugly and personal, and in a way that offers no substance to the debate."
"Mayor Giuliani is in the position where he has a solid record to talk about and unlike some candidates doesn't need to distract by resorting to negative attacks," said Maria Comella, a Giuliani spokeswoman.
One reason for the nastiness, whoever is at fault, is the lack of an established — and establishment-favored — front-runner in the eight-man Republican field. Modern-era Republican primary campaigns have tended to have one heir apparent — Eisenhower, Nixon, Ford, Reagan, the first Bush, Dole — which kept negative jibes to a minimum.
There are risks to going negative, especially in the crucial early-voting states of Iowa and New Hampshire, where such campaigns traditionally are anathema.
"In a crowded primary, there's a real danger if you attempt to take somebody out in a murder-suicide; people get disgusted and go somewhere else," said John Lapp, a Democratic strategist who ran then-Missouri Rep. Dick Gephardt's Iowa campaign in 2004 and witnessed such a phenomenon firsthand.
"Iowans tend to be more reserved and respectful," Squire said.
In the battle for the Democratic presidential nomination, Gephardt and former Vermont Gov. Howard Dean were leading in polls in Iowa until a few weeks before the state's kickoff caucuses. They went negative on each other in bruising rounds of speeches and TV ads. The bad blood was so prevalent that a Gephardt campaign staffer scuffled with a Dean staffer at a Gephardt event in Des Moines.
The result: mutual assured destruction for Gephardt and Dean, as above-the-fray John Kerry and John Edwards took two-thirds of the vote between them.
That may be happening again, this time on the Republican side.
In New Hampshire, McCain is rising again and competing for second place in most polls as Giuliani and Romney bloody each other. In Iowa, nice-guy Mike Huckabee, a former Arkansas governor, has risen in recent polls to compete for the lead.
"You've got Romney and Giuliani kicking each other in the gut," Lapp said. "And there's Mike Huckabee with bunnies and rainbows, heading toward the finish line."
Dante Scala, a political scientist at the University of New Hampshire, agreed: "John McCain could benefit from a food fight between Mitt and Rudy. He's a well-known commodity in New Hampshire, and voters may get sick of that and take another look at John McCain."
(William Douglas and David Lightman contributed to this article.)