Senate Majority Leader Harry Reid announced Thursday that he would file cloture today on the Employment Non-Discrimination Act (ENDA), setting up for a full vote in the Senate on Monday.

According to BuzzFeed, the motion to proceed could be filed within hours. It requires 60 votes.

“After months of lobbying and meetings with the overwhelming majority of Republican Senate offices, we're confident we have the 60 votes to defeat any attempted filibuster,” said Tico Almeida, founder and president of Freedom to Work, which is lobbying for passage of the measure. “We're keeping the pressure up with phone-banking in key states to help thousands of registered voters patch-through and urge Yes votes from key senators in Arizona, Nevada, New Hampshire, Ohio and Pennsylvania. It's long past time the Senate approved LGBT workplace protections.”

Three Democratic senators fell in line after Reid announced on Monday that ENDA would receive full consideration on the Senate floor. Senators Joe Manchin of West Virginia, Mark Pryor of Arkansas and Bill Nelson of Florida endorsed the measure this week.

ENDA, which was first proposed in 1994, seeks workplace protections based on sexual orientation and gender identity. The measure cleared a Senate committee with the help of three Republicans in July.

A possible fourth Republican vote could come from Ohio's Rob Portman, who earlier this week said he was leaning in that direction. Portman announced in March his support for marriage equality. He said he reversed his stance after learning that his son is gay.

Also aiding the bill is Thursday's swearing in of New Jersey Senator Cory Booker, a vocal supporter of LGBT rights.

(Related: Gay ally Cory Booker sworn into U.S. Senate.)