Later today, President Obama will speak at the LGBT Pride Month Reception at the White House. It’s my bet that Obama will call on Congress to pass the long-sought Employment Non-Discrimination Act, which would make hiring discrimination on the basis of sexual orientation illegal for all but the smallest employers.

It hasn’t attracted the attention it deserves, but Harry Reid recently promised a vote soon on the legislation, which has been stalled in Congress for many years. Reid also said he expects a markup on the bill in committee after the July 4th recess. So expect Obama to call tonight for Congress to act on it.

It’ll be particularly interesting to see how this is greeted in Congress, now that the politics on gay rights has shifted under the feet of our public officials to such a seismic degree. Indeed, at a time when the GOP is trying — ostensibly, at least — to moderate its image as more tolerant and inclusive, ENDA could confront Republicans in Congress with an absolutely awful vote.

The RNC autopsy already recognized that the party needs to reckon with the generational differences that exist on questions about gay rights. Yet soon after that autopsy was made public, the RNC reaffirmed its opposition to gay marriage as the party position.

But theoretically, the measure to oppose discrimination on the basis of sexual orientation should be less controversial than gay marriage, since it isn’t larded with the cultural, religious, and social land mines that made the marriage debate so treacherous for so long. Ending this discrimination is a no-brainer, yet it hasn’t gotten a vote in Congress for years.

But things have changed dramatically in the last couple of years. Don’t ask don’t tell has been repealed. Obama came out for gay marriage last year. A stampede of Democratic Senators — and two Republicans — have since followed suit. The Supreme Court could possibly overturn the Defense of Marriage Act this month, giving the cause of civil rights another burst of momentum and reminding everyone of just how quickly the culture is shifting — which could possibly help make the political grounds more fertile for ENDA.

Is there any conceivable chance it could become law? Probably not. At least, not yet.

ENDA is co-sponsored by only two Republican Senators — Susan Collins and Mark Kirk. It’s possible it could pick up a few more Republicans. What about the House? That will be far harder. But the prospect of House Republicans lining up against ending hiring discrimination against gays — or of conservatives in the Senate filibustering it — can’t be an appetizing one to GOP strategists preoccupied with broadening the party’s appeal. And remember: House Republicans caved on the Violence Against Women Act.

To be clear, Obama could actually do something right now about anti-gay workplace discrimination. He could sign an executive order barring such discrimination by federal contractors, something that gay rights advocates remain very angry at him for failing to do so far. And one hopes he will say something about his intentions in that direction tonight.  But if Congress really does take up ENDA, and it gets killed in the Senate or in the House, the argument for acting by executive order will be even stronger.

The bottom line is something will probably happen this year on anti-gay workplace discrimination. Even if it’s not as much as we’d like, the march towards full equality will continue.