Maria Cantwell – The Progressive Democrat

Ranking member Senator Maria Cantwell (D-WA) and committee chairman Senator Lisa Murkowski (R-AK) listen during a session of the Senate Energy and Natural Resources Committee on Capitol Hill January 8, 2015 in Washington, DC. The committee met for a markup of legislation to arrive the Keystone XL pipeline project. (BRENDAN SMIALOWSKI/AFP/Getty Images)

January 26, 2015 A key vote to advance legislation green-lighting the Keystone XL oil sands pipeline failed 53-39 in the Senate on Monday.

The vote aimed at cutting off debate on legislation to approve the controversial project fell short of 60 votes after Democrats, angry at Republicans for blocking debate on a slate of Democratic amendments last week, blocked the measure.

“Last Thursday night the majority decided that they would not allow for debate,” Democratic Sen. Ed Markey said on the floor ahead of the vote, echoing a complaint that a number of Democrats expressed on Monday after the Senate reconvened to debate the bill.

Senate Republicans have instigated a “gag-a-thon,” said Sen. Barbara Boxer, D-Calif.

Democratic Sen. Tom Carper of Delaware said he voted against ending debate because of the “failure of the majority to follow through on the open amendment process,” taking aim at Senate Majority Leader Mitch McConnell.