Usually liberal-minded Bay State voters provided a bright spot for McCain, who was battling in 13 states on Super Tuesday to stay competitive with Texas Gov. George Bush. The victory earned McCain the state's 37 Republican delegates.

"We have changed the face and shape of politics in America," said McCain, by telephone, to supporters gathered at a firefighters union hall in Boston's Dorchester neighborhood. "I want to thank you for all your hard work. I've very proud of our win in Massachusetts."

Meanwhile, many traditional Democrats cast their support for Gore as he sought to squash former Sen. Bill Bradley's hopes of remaining a contender in the Democratic primary. The two were vying for a share of the state's 118 Democratic delegates.

With 74 percent of the precincts reporting, Gore led 60 to 37 percent. On the Republican side, with 66 percent reporting, McCain led 65 percent to Bush's 32 percent and Alan Keyes' 3 percent.

In at least 10 states, Gore powered past Bradley, who appeared on the brink of dropping out. On the Republican side, Bush won in Missouri, Maryland, Maine, Ohio and Georgia, while voters in Vermont and Rhode Island favored McCain, according to early results.

Polls leading up to the Massachusetts primary showed most Republican ballots would go to McCain, even though the state's leading GOP figures -- Gov. Paul Cellucci and Lt. Gov. Jane Swift -- led the Bush campaign in Massachusetts.

Despite earlier boasts he would deliver the state for Bush, Cellucci more recently acknowledged that McCain could capitalize on the open primary system here as he did in Michigan, where he surprised and defeated Bush.

Open primaries allow unenrolled voters to cast ballots for any party.

But Cellucci said Tuesday that the independents' swing toward McCain wasn't necessarily bad for his candidate.

"In Massachusetts, the independents have flocked into the Republican party. It's good news today for John McCain, but it's also good news for George Bush in the fall," Cellucci said.

"We're going to work hard to keep them in the Republican Party," he said.

Gerald Racine, a retired firefighter, was one of those who typified McCain supporters in the Bay State. He's a longtime independent who would "rather vote for the man than the party."

"He sees things that need to be changed," Racine, 52, of Westfield, said of McCain. "He knows what people look for."

Bush, on the other hand, is "wishy-washy," Racine said.

Droves of unenrolled voters -- those not registered in any party -- supported McCain as expected. Since January, more than 21,700 Democrats dropped their party affiliation, helping push the percentage of unenrolled voters in the state to more than half for the first time.

Another 6,900 Democrats and unenrolled joined the ranks of the Republicans in time for the primary.

"From all indications, (McCain) has pulled in people who have not only changed parties to vote for him, but are voting for the first time because of him," said Jean Inman, head of McCain 2000 efforts in Massachusetts.

"They see something in John McCain that they find missing in the other candidates," she said.

Secretary of State William Galvin said Tuesday night that voters probably took a record number of Republican ballots, exceeding the 406,000 pulled in 1980 when voters chose from among Ronald Reagan, John Anderson and Bush's father, former President Bush. Galvin did not have final turnout totals.

"In general, it was a good day for democracy, at least in Massachusetts," Galvin said. "The surge of independents coming out was a very healthy thing. It might be taken as a wake-up call to the major parties."

Patrick Grace, 60, a bar owner from Somerville, said he preferred Bradley, but voted for Gore.

"I like Bradley, but I feel he doesn't have much of a chance. I felt I'd go with a winner," he said.

Alex Zaroulis, the New England campaign director for Gore 2000, said the extent of Gore's success -- even in states such as Maine and Vermont, where Bradley had strong support -- demonstrated that Democrats were united behind the vice president.

"It shows how strong a candidate Al Gore is," said Zaroulis, who had gathered with other Gore supporters at the Exchange, a restaurant in Boston.

Barbara Opacki, Bradley's state campaign director, said his supporters had gathered at the Bull and Finch Pub in Boston, but the party broke up before 10 p.m. when the outcome became clear.

"It's an early night," Opacki said.