Timing is everything in Congressional politics. And the timing should have been perfect for the women’s lobby — or at least that’s what the group thought as the Senate took up the Lilly Ledbetter Fair Pay Act on Wednesday night.

Teed up in honor of Tuesday’s Equal Pay Day, the Senate’s decision to vote on a pay discrimination bill was expected to be a rare legislative victory in a chamber where business has slowed to a near halt. The added presence of the Democratic presidential contenders, Sens. Hillary Rodham Clinton (N.Y.) and Barack Obama (Ill.), swooping in to help overcome a Republican filibuster threat built anticipation among civil rights groups that passage was near.

At issue is a Supreme Court decision last May that made it much harder for employees to sue for pay discrimination. In a case brought by Lilly Ledbetter, a former manager at a Goodyear Tire & Rubber Co. plant, the court found that a pay discrimination claim must be filed within 180 days of the alleged discriminatory act, despite the fact that pay discrimination is not always immediately obvious.

The ruling overturned what had been the Equal Employment Opportunity Commission’s standard interpretation of the time frame during which a lawsuit could be filed: 180 days after any paycheck that reflects the initial discriminatory payment, even if that were years earlier.

The bill would have returned the law to where it stood before the Supreme Court decision, but it came up four votes shy of the 60 votes needed to defeat a GOP filibuster. (Senate Majority Leader Harry Reid [D-Nev.] voted against cloture because that would allow him to bring the bill to the floor at a later date).

The bill marked the latest in a series of women’s issues that have stalled in the Senate, including raising the minimum wage, broadening access to contraceptives and most recently an anti-discrimination genetic research bill that had languished until last week because Sen. Thad Cochran (R-Miss.) put a hold on it. The Senate passed that bill unanimously April 24.

“They are both important votes,” Jonathan Parker, EMILY’s List political director, said of the Ledbetter bill and genetic research. “It’s clear the Republican Congress doesn’t get it. They have blinders on when it comes to issues that are really going to affect voters across the country, especially in this case that of women voters.”

While business groups applauded the Supreme Court’s decision, civil rights groups and the women’s lobby in particular rallied to combat the effort on Capitol Hill.

Just days after the Supreme Court’s ruling, a coalition formed under the umbrella organization the Leadership Conference on Civil Rights.

The National Women’s Law Center and the National Partnership for Women & Families took lead lobbying roles in a wide-ranging coalition that includes the American Civil Liberties Union, AARP and the NAACP Legal Defense and Educational Fund.

D.C. Del. Eleanor Holmes Norton (D), who ran the Equal Employment Opportunity Commission in the 1970s, was a big advocate on the House side, while in the Senate, Clinton and Sen. Edward Kennedy (D-Mass.) were early leaders.

Business interests, including the U.S. Chamber of Commerce, the National Federation of Independent Business, the National Association of Manufacturers and the Society of Human Resource Management worked to thwart the legislation.

Despite those groups’ best efforts, the House passed the Ledbetter bill last July, 225-199. Following the vote, both sides turned their attention to the Senate, redoubling efforts in mid-April.

“In the last several weeks lead groups combined their communications and resources,” said Lisalyn Jacobs, head of the Washington office for Legal Momentum, a nonprofit that focuses on women’s legal issues. That included not only grass-roots work in key states with relatively liberal Republican Senators, such as Maine’s Susan Collins and Oregon’s Gordon Smith, but also holding meetings on the Hill with a broad range of organizations.

They were able to pick up Smith and Collins (Maine’s other Senator, Republican Olympia Snowe, was an early supporter) as well as Minnesota Republican Sen. Norm Coleman. Still, they weren’t able to garner the 60 votes needed for cloture. (Republican presidential candidate Sen. John McCain [Ariz.] did not come back for the vote).

“The employer community was relieved with the vote last night,” said Michael Layman, manager of labor policy for the human resources trade group. “Certainly we will be keeping an eye on the Ledbetter legislation and it potentially appearing in another vehicle this year.”

Likewise, Michael Eastman, who headed the U.S. Chamber of Commerce’s efforts, said they were vindicated in the vote. “I think if this was a vote on substance rather than a cloture vote we might have been having a lot more discussion.” Eastman said the ad hoc business coalition is looking at putting together legislation that would be a compromise, although he declined to provide any specifics.

The defeat led Sen. Barbara Mikulski (D-Md.) to give an impassioned speech on the floor, calling for another vote.

“I stand here today to say: Do not forget the ladies because we will foment a revolution of our own,” said Mikulski, invoking the words of President John Adams’ wife, Abigail Adams.

“When we tell it, we are going to say: Call to arms, women of America, put your lipstick on, square your shoulders, suit up. We have a hell of a fight coming, but, boy, are we ready. The revolution starts tonight.”

Her call was echoed by the women’s lobby.

“[The vote] was frustrating, yes. Surprising, no,” said Kim Gandy president of the National Organization for Women. “It’s very clear that the Democrats don’t have a majority that allows them to win these fights.”

Many groups said they will use their grass-roots network and campaign contributions to make this a key issue in November.

Parker says EMILY’s List, for one, plans to highlight North Carolina Sen. Elizabeth Dole’s (R) vote against the bill. “I think this is another example of how Liddy Dole has lost touch with women voters,” Parker said.

The group is heavily involved in supporting Dole’s opponent, North Carolina state Sen. Kay Hagen.