Ira L. Black - Corbis via Getty Images The Equality Act would add gender identity and sexual orientation to existing federal nondiscrimination laws covering such realms as employment, housing, education, and public spaces and services.

NEW YORK (AP) — The LGBT rights movement’s top legislative priority, a comprehensive nondiscrimination bill, will be introduced in Congress on Wednesday, but the excitement will be tempered by political reality: The bill could well be doomed, at least for this year, by lack of Republican support.

That dynamic mirrors the situation nationwide. Twenty mostly Democratic-run states already have comprehensive nondiscrimination protections for LGBT people, comparable to what the Equality Act would mandate nationally. The protections extend to employment, housing, public accommodations and public services.

The other 30 states — where Republicans hold full or partial power — have balked at taking that step, illustrating that LGBT rights is as polarized along partisan lines as abortion, climate change and other hot button issues.

The result is a patchwork map in the U.S., with a majority of states making it legal for an LGBT person to be fired, evicted or barred from public facilities because of sexual orientation or gender identity.

“No one’s civil rights should be dependent on what ZIP code they live in,” said JoDee Winterhoff of the Human Rights Campaign, a national LGBT rights group.

Opponents of nondiscrimination bills, meanwhile, say that such measures can infringe on religious and other beliefs.

“The Equality Act would undermine the freedom to think and act according to our beliefs,” said Emilie Kao of the conservative Heritage Foundation. Citing recent cases in the news, she said faith-based adoption agencies should be not be required to serve same-sex couples, and entrepreneurs such as bakers and florists should be not be required to provide their services for same-sex weddings.

The Equality Act was first introduced three years ago; it would add gender identity and sexual orientation to existing federal nondiscrimination laws covering such realms as employment, housing, education, and public spaces and services. The new version specifies that the act would cover retail stores, emergency shelters, banks, transportation, pharmacies and legal services.

In Congress, the bill has near-unanimous Democratic backing and seems certain to pass the House, but as of Tuesday afternoon only one Republican, Rep. Brian Fitzpatrick of Pennsylvania, had announced plans to be a co-sponsor. In the GOP-controlled Senate, the bill’s chances appear slim.

“The path forward may require another election,” said James Esseks, director of the American Civil Liberties Union’s LGBT & HIV Project.

Esseks is hopeful that federal courts may broaden some protections for LGBT people, notably with regard to workplace discrimination. But he says the Equality Act eventually will be needed to “fill all the gaps” and provide comprehensive protections in conservative states that are unlikely to enact LGBT rights bills on their own.

This year, LGBT nondiscrimination bills have been filed in more than dozen state legislatures where the GOP either is in full control or, in the case of Virginia, controls one chamber. Two such bills passed Virginia’s Democratic-controlled Senate, but GOP leaders in the House of Delegates refused to consider them. None of the bills in other states appear headed for passage.

Some examples:

— In West Virginia, the state Senate’s GOP leadership let an LGBT nondiscrimination bill die without a hearing, despite a plea from 12 mayors to consider it.

— In North Dakota, a measure that would prohibit housing or workforce discrimination based on sexual orientation was defeated in the House by a 70-22 vote.

— In Arkansas, the state Supreme Court refused to let the city of Fayetteville enforce a local ordinance banning discrimination based on sexual orientation or gender identity. The court cited a state law aimed at preventing local protections for LGBT people.

— In Arizona, LGBT activists considered it a breakthrough when two GOP lawmakers signed on as sponsors of a nondiscrimination bill. But the measure failed to advance; it was denounced by the conservative Center for Arizona Policy as a threat to individuals and organizations “who have a historic understanding of marriage and gender.”

For LGBT activists, the biggest victory this year came in New York, where the legislature expanded existing nondiscrimination protections to cover transgender people. Republicans controlling the state Senate had long blocked that move, but Democrats took over the chamber in November’s midterm elections.

Until 2015, when the U.S. Supreme Court legalized same-sex marriage nationwide, marriage was the dominant issue animating opponents of LGBT rights.

Since then, LGBT nondiscrimination laws and full civil liberties for transgender people have taken center stage. Opponents of the latter say they can be problematic in terms of access to public restrooms and locker rooms, as well as transgender women’s participation in some competitive sports.

LGBT activists, citing numerous national polls, say a solid majority of Americans support nondiscrimination protections for LGBT people. So do many big business — the Human Rights Campaign has compiled a list of more than 160 major corporations supporting the Equality Act, ranging from American Airlines and Coca-Cola to General Motors and Microsoft.

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