A RealClearPolitics.com average of several polls Thursday indicated Romney has a 44-percentage point average lead over his rivals.
State GOP deputy chairman Peter Blute, a former U.S. representative, told The Boston Globe he supports Romney, saying he has "broad appeal" and gives Republicans a chance to defeat President Obama in November.
Because Romney once led the Bay State, Blute said, "We know him, we know his wife, we know his family. He's been a guy who's just a successful person in public and private life."
Romney won Massachusetts in the 2008 GOP presidential primary with 51 percent of the vote, while Sen. John McCain of Arizona came in second with 41 percent.
State GOP chief Robert Maginn, who worked for Romney at Bain Capital and has helped him in all his political campaigns, said the former Massachusetts governor has "almost 100 percent" support among elected officials. He also told the Globe if Romney wins the party nomination, more Massachusetts Republicans will vote on Election Day, helping down-ticket candidates.
"He'll have coattails," Maginn said. "People will start to say we need some balance, we need to send people from the Republican Party to the congressional delegation, to Washington."
He went further, saying he thought Romney could make Massachusetts competitive in the general election, though President Obama, a Democrat, won the state with 62 percent of the vote in 2008 against McCain.
Fred Bayles, the director of the Boston University College of Communication's State House Program, said lingering question would be whether Romney will inspire voters, who for any number of reasons, aren't turning out at the polls.
"People are turned off by the process," Bayles said. "They're not energized like they were in 2008, and you have a lot of negative ads, which I think convince the voters that none of these guys are worth voting for."
Just before the primary, Secretary of State William Galvin said Massachusetts has about 80,000 fewer registered voters than it did October 2010, a month before the last statewide election, Wicked Local in Gloucester, Mass., said.
The state's top election officer said Massachusetts had 4,111,128 registered voters as of Feb. 15, -- the deadline to register to vote in the primary -- compared to 4,190,907 on Oct. 13, 2010, for a 1.9 percent drop.
The number of registered Democrats fell by 3.5 percent, or 53,095, for the same period, Galvin said. The number of Republicans was down 1.8 percent, or 8,367, during the 16-month period.
Democrats still hold an advantage over Republicans in Massachusetts, with 35.9 percent of registered voters compared to 11.35 percent for the GOP.
Secretary of State spokesman Brian McNiff said the drop-off in registered voters could be attributed to deaths and to people who moved out of state, Wicked Local said. He predicted the numbers will increase as Election Day nears, particularly since 2012 is a presidential election year.
"You'll see it pick up," McNiff said.
Forty-one delegates are up for grabs in the proportional Massachusetts primary.