WASHINGTON — A former Massachusetts governor, Mitt Romney, is off to a faster fund-raising start than either of his better-known and heavily favored rivals for the Republican presidential nomination, Mayor Giuliani and Senator McCain.

Mr. Romney’s campaign said yesterday that he raised $20.63 million in the first quarter of 2007, easily outpacing Mr. Giuliani, who reported raising $15 million, and Mr. McCain, who took in $12.5 million. All three trailed Senator Clinton, who reported Sunday raising $26 million during the first quarter, a period that has seen fund-raising records fall in both major parties.

The cash totals appeared to damage Mr. McCain’s campaign as much as they helped Mr. Romney. The Arizona senator has been laying the groundwork for a second White House bid for years and had been considered the Republican front-runner until Mr. Giuliani shot past him in the polls earlier this year. Although Mr. McCain had been trying to lower expectations in recent days by suggesting he did not like fund raising, his campaign acknowledged disappointment in releasing its first quarter figures yesterday.

“Although we are pleased with the organization we’ve built, and polls show us strongly positioned in key primary states, we had hoped to do better in first-quarter fund raising,” Mr. McCain’s campaign manager, Terry Nelson, said in a statement. “We are already in the process of taking the necessary steps to ensure fund-raising success moving forward.”

The release of the much-awaited numbers came with spin from each of the campaigns. “Governor Romney’s fund-raising totals are indicative of the extraordinary success he has had reaching out and discussing important issues with the American people,” his spokesman, Kevin Madden, said in a statement.

Yet while Mr. Romney’s fundraising prowess will cement his

position in the top tier of Republican candidates, it also will increase pressure for him to demonstrate that he is connecting with voters. His campaign has been mired in the single digits in most polls, below a former speaker of the House, Newt Gingrich, and a former Tennessee senator and actor, Fred Thompson, both of whom have not entered the race.

“You’ve got to give him credit for that,” an unaffiliated Republican consultant, Rich Galen, said of Mr. Romney’s first-quarter take. “But at some point you have to ask them, ‘How do you intend to turn the money into votes?'”

Mr. Romney, a wealthy former businessman who left his Massachusetts post in January, loaned his campaign $2.35 million in start-up funds, bringing his total to $22.98 million. His campaign did not say how much cash it has in hand, leaving open the question of what Mr. Romney has already spent. The same was true for Mr. McCain.

While it finished well back of Mr. Romney’s, Mr. Giuliani’s team focused on its $10 million total for March alone, saying the former mayor got off to a “late start” but proved he could raise a lot of money quickly. “Considering our late start, we are very pleased by the pace raised in March and see it as a positive indication of what’s to come,” the campaign manager, Michael DuHaime, said.

An aide to Mr. Giuliani later noted that while the campaign did have a major fund-raiser in December, 36 of its 57 total events occurred last month. The campaign has raised $17 million altogether, including receipts from the December event and funds transferred from Mr. Giuliani’s aborted Senate campaign in 1999. The campaign has more than $11 million in hand, almost all of which can be legally spent during the primary, officials said.

The only major candidate who has not disclosed first quarter fund-raising totals is Senator Obama of Illinois, who is expected to come close to matching Mrs. Clinton’s record-breaking total. An announcement could come as early as today.