There are now more than 4.3 million enrolled voters in Massachusetts. The majority of those — close to 53 percent — are independent voters who opted not to enroll in any major party.
Of the remaining voters, nearly 36 percent are registered Democrats and another 11 percent are Republicans.
Since February, Democrats have added nearly 76,000 new voters while Republicans have added nearly 18,000 and more than 138,000 independent voters have added their names to the rolls.
The jump in enrollment comes as former Massachusetts Gov. Mitt Romney is challenging President Barack Obama and incumbent Republican U.S. Sen. Scott Brown is trying to fend off a challenge from Democratic hopeful Elizabeth Warren.