WASHINGTON — Two days before he is set to reintroduce the long-standing bill to prohibit anti-LGBT job discrimination on Thursday, the Senate's lead sponsor of the Employment Non-Discrimination Act is pushing an ambitious — if extremely optimistic — agenda that could end with the bill being sent to President Obama's desk to be signed into law.

Talking with BuzzFeed Tuesday morning, Sen. Jeff Merkley of Oregon said he expects a Senate markup of ENDA by early summer, believes supporters will meet the 60-vote threshold for Senate passage, and even holds out hope for House action on the bill to outlaw anti-LGBT job discrimination.

"We'll be introducing it on Thursday. We'll have Sens. [Tom] Harkin and [Tammy] Baldwin and myself on the Democratic side and Sens. [Susan] Collins and [Mark] Kirk" on the Republican side, he said. "I feel like there's a lot of momentum behind this effort."

Harkin is the chairman of the Senate's Housing, Education, Labor and Pensions Committee that will be considering the legislation.

"We will have both a hearing and we will have a markup. It hasn't been marked up in committee since 2002," Merkley said, noting, "Sen. Harkin has said he wishes to do it as soon as possible. I think that, realistically, we have a shot of getting this done in May. ... It would be my hope for us to have a markup in May or June."

As for the full Senate, Merkley added, "I think we have a very good chance of meeting even the higher 60-vote test, if you will, for ending discrimination in employment."

Merkley said he has spoken with several Republican members beyond Kirk and Collins, although he would not say who they were, broadly noting, "I do feel like there is a warming feeling, a sense of momentum when it comes to folks' willingness to take a stand against discrimination."

But, even if the Senate were to act on the bill, the House Republican leadership has not supported the legislation in the past. Merkley's office said that Reps. Jared Polis and Ileana Ros-Lehtinen will be reintroducing ENDA Thursday in the House as well.

Asked if he thinks there's any chance of the bill moving in the Republican-led House, Merkley said, "I do. I think if you have a bill that goes through the Senate, has met the higher 60-vote test — if we have a bipartisan vote coming out of the Senate, I think it sends a strong message to the House that it's time to consider this."

"I think there's a very good chance that the House will decide to take it up," he said, citing the House's approval of the Violence Against Women Act reauthorization earlier this year.