Senate Majority Leader Harry Reid (D-Nev.) officially set up a Monday vote for the Employment Non-Discrimination Act by filing cloture for the bill on the Senate floor Thursday evening.

Reid made the announcement on the Senate floor with little fanfare before he moved on to other business and adjourned the Senate until Monday at 2 pm.

Faiz Shakir, a Reid spokesperson, estimated the cloture vote on ENDA will take place around 5:45 on Monday and a final vote will take place sometime on Wednesday.

By filing cloture on the bill, Reid starts for the time period for when cloture vote will take place to enable the bill to move to the floor. After filing for cloture, the vote will take place after an intervening day and one hour pass. For a successful vote on cloture, 60 votes are required in the Senate.

After cloture is invoked, up to 30 hours of debate can take place before a vote happens on final passage, which requires a simple majority. But the vote for final passage could take place sooner if both parties agree to give up the time.

Confidence persists there are at least 60 votes in the Senate to invoke cloture on ENDA. All 55 members of the Senate Democratic caucus support ENDA, and there are two Republican original co-sponsors: Susan Collins (R-Maine) and Mark Kirk (R-Ill.). Assuming the two Republicans who voted in committee for ENDA, Sens. Orrin Hatch (R-Utah) and Lisa Murkowski (R-Alaska), vote for cloture as well, only one more vote is required to move forward with ENDA.

Tico Almeida, president of Freedom to Work, expressed confidence in a statement sufficient votes are in place to pass ENDA.

“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,” Almeida said. “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.”

During a taped interview on The Rachel Maddow Show that aired Wednesday, Reid expressed confidence there would be enough votes to invoke cloture on ENDA. Noting that all 55 Democrats are on board, Reid predicted “we’re going to get a least five Republicans” to reach 60 votes.

Other Republicans seen as possible “yes” votes on ENDA are Sens. Jeff Flake (R-Ariz.), John McCain (R-Ariz.), Dean Heller (R-Nev.), Kelly Ayotte (R-N.H.), Rob Portman (R-Ohio) and Pat Toomey (R-Pa.). However, Flake this week told the Blade he’s voting “no” because of the transgender protections in the current version of the bill.

The Human Rights Campaign, and the $2.5 million Americans for Workplace Opportunity campaign it helped organize, is also touting its action in anticipation of an ENDA vote.

According to HRC, 30 field organizers in New Hampshire, West Virginia, Ohio, Arizona, Arkansas, Nevada and Pennsylvania have generated over 200,000 constituent contacts in favor of ENDA. Additionally, grassroots organizers have held 150 events in these critical states generating over 108,000 emails, 78,000 postcards, 13,000 calls and 800 letters, HRC says.

But anti-gay forces are also being outspoken against ENDA as the vote approaches.

Tony Perkins, president of the Family Research Council, railed against the LGBT legislation in a statement, saying the bill “threatens the free market, undermines employers’ rights, and violates the free exercise of religion.”

“The vast majority of employers would not consider an employee’s sexual orientation relevant or even want to know about an employee’s sex life,” Perkins said. “However, ENDA would transform the workplace into an environment in which certain sexual lifestyles are given a special status by the federal government and religious expression is suppressed.”

The vote will be historic in many ways. It will the first time the either chamber of Congress has considered a version of ENDA that includes transgender workers. It’s also the first time the Senate has considered ENDA since 1996, when the legislation failed by one vote.

Amendments to ENDA are expected. Senate Health, Education, Labor & Pensions Committee Chair Tom Harkin (D-Iowa) told the Blade, “There’ll be some amendments, yeah.” Harkin added he doesn’t know what the nature of the amendments will be.

Sen. Jeff Merkley (D-Ore.), chief sponsor of ENDA, also expressed excitement over the possibility the Senate approving legislation to end job bias against LGBT workers.

“We have a chance next week to pass a landmark civil rights bill that will enshrine in law an issue of fundamental fairness: no one should be fired for their sexual orientation or gender identity,” Merkley said. “Discrimination is just plain wrong. Everyone should have the freedom to work hard and earn a living. I am pleased that the U.S. Senate will consider this fundamental issue of equality under the law.”