"At this stage, I spend less time trying to analyze the past and more time trying to assess where we go from here," said Romney, who supports the recent surge of troops into Baghdad and Anbar Province and said he is eagerly awaiting Gen. David Petraeus's progress report in the fall.

With his movie star looks and presidential bearing, the increased visibility for Romney is beginning to put him on the receiving end of his opponents' ire and the media's scrutiny. Political observers have suggested that voters would be unwilling to elect a Mormon to the nation's highest office. Already, the other Republican campaigns are quietly questioning his foreign policy credentials and not-so-quietly criticizing his changing policy positions.

"The question for voters is, does a one-term governor from Massachusetts have the foreign policy experience necessary to deal with the challenges of today's world?" said Brian Jones, McCain's spokesman.

Romney's newfound success appears to be a source of irritation to his opponents. In South Carolina's debate last week, McCain leveled a sarcastic dig at the former governor, suggesting he changes his positions depending on whether it is an even-numbered year or what office he is seeking.

And Romney has changed numerous, significant positions from his stance on abortion (to anti-abortion), to his newly minted support for gun rights and opposition to gay marriage, to his largely curtailed support for embryonic stem cell research. "After studying presidential nominations for 30 years, I've never seen somebody who has so completely renounced his past record when he decided to run for president," said William Mayer, a political scientist at Northeastern University in Boston.

Romney has grown used to such criticism, and depicts his changes as evolution rather than flip-flopping.

"Everyone hopefully changes when they get experience on some issues," he said in the interview. "You don't change your principles, but your view on a particular issue may change."

That hasn't stopped the McCain campaign from taking shots at Romney. "Mitt Romney has been consistent in one regard: that nearly every position he holds now is opposite of what it was when he was governor of Massachusetts," Jones said.

With his campaign gathering steam, Romney is in the midst of another intense burst of fundraising. On Monday, he raised money in three states, starting in Hartford, Conn., and traveling to Boston and then Houston, Texas. Here at Fenway Park, approximately 200 donors paid $2,300 apiece for a lunch of hot dogs with sauerkraut, chicken and potato salad.

In June alone, Romney is scheduled to hold 65 fundraisers.