Romney accuses McCain of using Nixon-style campaign tactics

Mitt Romney accused his rival John McCain of adopting underhanded tactics from Richard Nixon, the GOP president who resigned in disgrace.

"I don't think I want to see our party go back to that kind of campaigning," Romney said in his most pointed rebuttal yet to front-runner McCain's claim that the former Massachusetts governor favors a timetable for withdrawing troops from Iraq. Romney denies this charge and most media analyses have concluded that Romney wasn't using 'timetable' in the same way Democratic candidates have.

McCain adviser Steve Schmidt responded that Romney "is lashing out because he's unable to defend his comments about a timeline, albeit a secret one."

Both camps readied ad campaigns for the Super Tuesday contests in 21 states. Each campaign has been precisely targeting their commercials to states that they think they can win and that offer them the most delegates. The candidates were working out their final strategies on Thursday.

California Gov. Arnold Schwarzenegger endorsed Sen. John McCain on Thursday, praising him as an extraordinary leader who can reach across the political aisle to get things done.

"He is a great American hero and an extraordinary leader," Schwarzenegger added about the fighter pilot who was downed in North Vietnam and spent years as a prisoner of war.

Schwarzenegger said he made his decision to endorse McCain after former New York City Mayor Rudy Giuliani withdrew from the race and endorsed McCain.

He said both McCain and Giuliani "are friends of mine, and so this is why I really didn't want to endorse anybody."

The Arizona senator also won the backing of Texas Gov. Rick Perry, who had endorsed Rudy Giuliani.

Mayor Michael Bloomberg once again denied any presidential aspirations Thursday, but with some new language that suggests he might really mean it this time.

"I've said repeatedly I'm not a candidate ... and I'll stay that way," he said in response to a reporter's question during an appearance at Google's New York headquarters.

Democrat Barack Obama and Republican Ron Paul are the latest presidential candidates who plan to reach out to young voters through an interactive forum Saturday sponsored by MySpace, MTV and the Associated Press. The candidates will answer questions posed by online viewers or from a live audience at MTV's studio in New York.