(CNN) Thirty-one Democratic male senators have sent a letter to Senate leaders calling on them to move on sexual harassment legislation that would overhaul how claims are handled on Capitol Hill.

"If we fail to act immediately to address the systemic problem in our own workplace, we will lose all credibility in the eyes of the American public regarding our capacity to protect victims of sexual harassment or discrimination in any setting," said the letter, sent to Senate Majority Leader Mitch McConnell, R-Kentucky, and Minority Leader Chuck Schumer, D-New York.

The effort, organized by Sen. Jeff Merkley of Oregon, received the support of every male Democratic senator, minus Schumer, a recipient of the letter.

But notably the letter failed to get a single Republican senator to sign on, despite what Democratic congressional aides say was an effort to make it bipartisan.

A Democratic congressional aide tells CNN they were expecting Republican Sen. Ted Cruz of Texas, one of the cosponsors of the legislation, to sign on to the letter -- but he changed his mind and did not in the end.

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