Updated

Republican Mitt Romney on Thursday defended his series of shifts on issues, arguing that his top rivals for the Republican presidential nomination also have histories of switching positions.

"I served as governor for four years and my record is consistent and clear," the former Massachusetts governor told The Associated Press in an interview. "I'd also note that everybody in this race that I know has changed their mind on certain positions and they've done so as they gained more experience."

He singled out Sen. John McCain of Arizona and former New York City Mayor Rudy Giuliani, both of whom lead Romney in national polls.

"Senator McCain voted against the Bush tax cuts. Now he's for them. He was opposed to ethanol. Now he's for it. He said he was opposed to overturning Roe v. Wade. Now he's for overturning Roe v. Wade," Romney said, adding: "that suggests that he has learned from experience."

"Mayor Giuliani has made a number of changes over his career, and there are places where I've made changes," Romney said. On his clearest flip — on abortion — Romney said: "I'm not going to apologize for saying I was wrong and now I think I'm right."

Romney made the remarks in a 15-minute interview as he traveled from Hampton, New Hampshire, where he talked about homeland security issues with local law enforcement officials, to Stratham, New Hampshire, where he greeted a crowd outside a home-and-garden store.

He highlighted his rivals' records a week before the three top-tier candidates — and seven other lesser-known hopefuls — meet in the first debate of the primary race.

In the interview, Romney also:

— Said the country would be safer by only "a small percentage" and would see "a very insignificant increase in safety" if Al Qaeda leader Usama bin Laden was caught because another terrorist would rise to power. "It's not worth moving heaven and earth spending billions of dollars just trying to catch one person," Romney said. Instead, he said he supports a broader strategy to defeat the Islamic jihad movement.

— Said "the jury's still out" on whether Iraqis, with U.S. help, will successfully rebuild their nation, and establish the rule of law and a permanent government. He ridiculed Democratic efforts to set a public date for withdrawal. "There's certainly nothing wrong with having milestones that we hope to achieve and having the military evaluating whether we're making progress or not, but to set a public deadline for departure makes no military sense at all."

For months, Romney has faced criticism for changing his positions on abortion and gay rights, and equivocating on a series of other policy issues, including immigration and gun control. He has cast himself as the conservative choice for voters, a contrast to the moderate views he voiced in an unsuccessful 1994 Senate race and a victorious 2002 governor's race in liberal-leaning Massachusetts.

In the AP interview, he turned the spotlight on his rivals.

McCain opposed President Bush's tax cuts in 2001 and 2003, but now supports extending them because he says that doing otherwise would amount to a tax increase. The Arizona senator opposes ethanol subsidies, although he backs production of the corn-based fuel. In contrast to the 2000 campaign, McCain now is stressing fuel production as he looks toward the early voting state of Iowa.

McCain has a consistent anti-abortion voting record but once, in 1999, he told an interviewer that he opposed overturning the landmark Supreme Court case that legalized abortion.

As a big-city mayor, Giuliani once advocated strong federal gun controls, including a nationwide mandate to register handgun owners. He now emphasizes the Second Amendment and state-by-state solutions to gun violence. Giuliani is a solid proponent of abortion rights. In the 1990s, he opposed a late-term abortion procedure but last week issued a statement praising the Supreme Court's decision to uphold a ban on what critics call partial-birth abortion.

McCain's aides did not immediately comment. Giuliani's spokeswoman Katie Levinson simply said: "Mayor Giuliani continues to have the utmost respect for the former governor."

The Romney campaign said Thursday that a former counterterrorism chief who served during the Sept. 11 terrorist attacks has joined the campaign as a senior adviser.

Cofer Black served as the director of the CIA Counterterrorism Center during the attacks and was singled out for especially harsh criticism by the agency's inspector general in a 2005 report on faulty intelligence efforts before the attacks.

Black has worked for the past two years as vice chairman of Blackwater USA, a North Carolina-based security firm which specializes in private security and private military services.

Earlier this year, Black announced he had formed a new company called Total Intelligence Solutions, which focuses on providing intelligence gathering to companies. Its services will include rooting out insiders who are causing harm.