Last June, Senate Republicans filibusteredAi??and killed the Paycheck Fairness Act, which was designed to make sure women can get equal pay for equal work at their jobs.

One of the Senators who joined this filibuster effort was Scott Brown (MA). Brown — who, remember, is running misleading commercials claiming he is a friend to women voters — told the mediaAi??the bill would’ve placed “job-killing burdens on small businesses.”

But what the media didn’t report was that many of the same Big Business front groups and lobbyists that battled the bill behind the scenes have spent hundreds of thousands of dollars to re-elect Brown since he helped kill fair pay for women.

In the days leading up to the Senate vote for the bill, corporate lobbyists from groups like the U.S. Chamber of Commerce and Grover Norquist’s Americans for Tax Reform (ATR) lined up to oppose it. One group, theAi??Society for Human Resource Management, mobilized human resources officers at corporate firms to lobby senators to kill the bill.

The resulting filibuster ended up killing the bill, in a blow to women everywhere who are discriminated against in the workplace. But as is often the case in Washington, the vote was just the beginning. The payoff was what senators like Brown were waiting for.

Before the vote, Brown received $238,028 from interests opposed to the bill. But in his campaign against bold progressive Elizabeth Warren, the real payday arrived. Two weeks ago, Norquist’s ATR dropped $162,000 on mailers attacking Warren on behalf of Brown.

Last week, the U.S. Chamber of Commerce — which has in the past been caught taking funding from overseas corporations like the state-owned Bahrain Petroleum Company — spent $300,000 to hire Meridian Strategies, a firm based in the Washington, D.C. area, to produce and send mailers attacking Elizabeth Warren.

These are just two of the most prominent groups of corporate lobbyists that opposed the Paycheck Fairness Act who are now bankrolling Brown. Others include the so-called National Federation of Independent Business, Food Marketing Institute, and National Restaurant Association.

Remember also that certain outside groups like Karl Rove’s Crossroads GPS are also spending big to support Brown and attack Warren, but we don’t even know which corporations finance that group because of the special tax status that it can claims. Conveniently, Brown filibustered and killed the DISCLOSE Act, which would’ve forced Rove to disclose all of his corporate and billionaire donors.

Massachusetts deserves better than a Senator who sells out fair pay and equal rights for women for lobbyist cash. Click here to sign up to make calls for Elizabeth Warren.