Last week, the U.S. Senate killed the Paycheck Fairness Act, a proposed law that would have taken on salary imbalances between men and women in the U.S.

While a companion version of the bill passed in the House last year, Senate Republicans had filibustered the bill there. To override the filibuster and move the bill forward, supporters needed to win 60 votes; instead, they got only 58 votes, with Senate Republicans voting unanimously against the bill.

The Paycheck Fairness Act, which was first introduced by then-Sen. Hillary Clinton, would have made it easier for workers to sue employers and win damages for unequal compensation, and would have strengthened government responses to gender-based wage discrimination. The bill, backers argued, would have addressed disparities in men’s and women’s wages in the U.S. According to 2009 federal Census data, women who work full time earn 77 cents for every dollar made by men doing the same work; the difference is even greater when the wages of African-American and Hispanic women are compared to those of their white male counterparts.

Supporters, including President Barack Obama, had hoped to see the act pass during the current lame-duck session, before the new, Republican-dominated Senate class is sworn in in January. Shortly before the Senate vote, the White House released a statement saying, “The persistent gap between men’s and women’s wages demonstrates the need for legislative change. This bill would address this gap by enhancing enforcement of equal pay laws.”

But in the end, senators apparently were more swayed by opponents of the bill, who contended it would lead to frivolous lawsuits and create an anti-business atmosphere that would hurt the economy. The Boston Globe, in a recent editorial, called the bill “too broad a solution to a complex, nuanced problem” and said it would unfairly place the burden of proof on employers accused of gender discrimination. “A narrower bill that would stiffen some penalties and ban retaliation would be helpful. But companies are right to be concerned that this bill, as written, is too deep an intrusion,” the paper argued.

Days before the bill, activists from MomsRising of the Pioneer Valley paid a visit to the Boston office of Massachusetts’ Republican senator, Scott Brown, to urge him to support the Paycheck Fairness Act. They brought with them clam-shaped cookies, to underscore their point: that women in Massachusetts, and around the country, aren’t bringing home enough clams in their paychecks.

Brown, alas, was not swayed by the creative lobbying effort, joining his GOP colleagues in killing the bill. (Massachusetts’ other senator, Democrat John Kerry, voted in support of the bill.) Also voting against the bill were Maine’s two female Republican senators, Susan Collins and Olympia Snow. Both had earlier voted for the related Lilly Ledbetter Fair Pay Act—the first law signed by Obama after his inauguration—and were being closely watched for their votes on the Paycheck Fairness Act.

The day after the vote, MomsRising called the Senate’s action “pathetic” and “outrageous.” The group also urged supporters to sign a letter to senators who opposed the bill, “asking them to explain to their daughters, and ours, why in 2010 women don’t deserve the right to equal pay for equal work.” (For information, go to www.momsrising.org.)