The constitutional amendment would restore the First Amendment and end unlimited outside spending in elections, according to the office of state Sen. Jamie Eldridge, lead sponsor of the resolution.

“In two short years, the Citizens United decision has upended our election system, and the voices of ordinary Americans risk being drowned out by the tens of millions of dollars that are being poured into attack ads paid for by corporate donors,” said Eldridge, D-Acton, whose district includes Marlborough, Hudson, Southborough, Westborough and parts of Northborough and Sudbury. “The problem is real, resulting in a strong grassroots effort across the Commonwealth coming together to support the only effective, long-term solution: passing a constitutional amendment that will overturn this misguided, destructive decision. I’m proud of the Senate, under the leadership of Senate President (Therese) Murray, for passing this resolution and sending a strong message that our democracy isn’t for sale.”

During the 2010 elections, the first since the Supreme Court’s decision, non-candidate spending reached nearly $400 million, about 60 percent higher than spending during the 2006 midterm elections, according to the Center for Responsive Politics.

“This is a growing problem that needs to be fixed,” Murray said. “Corporate spending has reached exorbitant levels and it is destroying the civility of the political process. We are facing a serious and direct threat to our democracy and I urge Congress to take immediate action.”

A poll of Massachusetts voters conducted in February by WHDH and Suffolk University revealed that 83 percent of Democrats, 73 percent of Republicans and 81 percent of independents oppose the Supreme Court’s decision, according to Eldridge’s office.

The Senate approved the resolution 35-1 and it now moves to the House.

“We are delighted that the Senate has taken bipartisan action to address this disastrous decision,” said Pam Wilmot, executive director of Common Cause Massachusetts. “A campaign for a constitutional amendment is no easy task, but the U.S. Supreme Court left us no choice. Only with a constitutional amendment can we address the problem of money in politics that it, and other decisions, has created. Passing this resolution has put Massachusetts on the forefront of that critical effort, which, as the cradle of liberty, is where we should be.”