"What we are submitting is the idea that the president should be selected by the majority of people in the United States of America," Senator James B. Eldridge, an Acton Democrat, said in introducing the bill, which was ultimately enacted by a 28-9 vote.
Under the new bill, he said, "Every vote will be of the same weight across the country."
But Senate minority leader Richard Tisei said the state was meddling with a system that was "tried and true."
"We've had a lot of bad ideas come through this chamber over the years, but this is going to be one of the worst ideas that has surfaced and actually garnered some support," said Tisei, who is also the Republican candidate for lieutenant governor.
The bill now heads to the governor's desk. A spokesman for Governor Deval Patrick said last week that the governor had "said in the past that he is supportive of the goals of the legislation, but as always he will review the legislation if and when it reaches his desk."
Under the law, which was enacted by the House last week, all 12 of the state's electoral votes would be awarded to the candidate who receives the most votes nationally.
Supporters are campaigning, state by state, to get such bills enacted. Once states possessing a majority of the electoral votes (or 270 of 538) have enacted the laws, the candidate winning the most votes nationally would be assured a majority of the Electoral College votes, no matter how the other states vote and how their electoral votes are distributed.
Illinois, New Jersey, Hawaii, Maryland, and Washington have already approved the legislation, according to the National Popular Vote campaign's
website.
Supporters of the change say that the current Electoral College system is confusing and causes candidates to focus unduly on a handful of battleground states.
Critics say the current system is not broken. They also point to the disturbing scenario that Candidate X wins nationally, but Candidate Y has won in Massachusetts. In that case, all of the state's 12 electoral votes would go to Candidate X, the candidate who was not supported by Massachusetts voters.
Tisei also criticized the proponents for not following the normal procedures to seek a constitutional amendment.
"The thing about this that bothers me the most is it's so sneaky. This is the way that liberals do things a lot of times, very sneaky," he said. "This is sort of an end run around the Constitution."
The measure passed both branches of the Legislature in 2008 but did not make it all the way through the process.
