Four Republican senators so far have broken with their party to support a bill codifying same-sex marriage

• The Senate is set to take a procedural vote Wednesday on a bill codifying same-sex marriage into law.
• Four Republican senators are publicly backing the bill so far, but more could emerge this week.
• Senators tweaked the bill, which sailed through the Democratic-controlled House in July, to get GOP support.

The Senate is set to take a procedural vote Wednesday on the Respect for Marriage Act, a bill that would codify same-sex and interracial marriage into federal law.

The bill, entitled the "Respect for Marriage Act," was first passed by the Democratic-controlled House in July amid concerns that the Supreme Court's overturning of Roe v. Wade in June might put marriage equality at risk as well.

In a concurring opinion to that ruling, which ended 50 years of a constitutional right to an abortion, conservative Supreme Court Justice Clarence Thomas suggested that the precedent underpinning same-sex marriage — which was legalized by the Court in the 2015 Obergefell v. Hodges ruling — should be "reconsidered" as well.

The bill garnered 47 Republican votes when it passed the House in July, but momentum slowed when it reached the Senate, where Republicans expressed concerns about religious liberty protections.

A group of bipartisan senators that included Democratic Sens. Tammy Baldwin of Wisconsin and Kyrsten Sinema of Arizona — the only two openly LGBTQ members of the chamber — amended the legislation to assuage Republicans, releasing new bill text on Monday.

A Gallup poll from June 2021 found that 70% of Americans — including 55% of Republicans — support same-sex marriage.

A vote had originally been planned before the November midterm elections, but was ultimately delayed at the request of the bipartisan group, which included Republican Sens. Susan Collins of Maine, Rob Portman of Ohio, and Thom Tillis of North Carolina.

There are a range of other Republicans who could support the bill, but who haven't officially said so. Republican Sen. Lisa Murkowski of Alaska is broadly supportive of same-sex marriage, while retiring Republican Sens. Roy Blunt of Missouri and Pat Toomey of Pennsylvania have declined to state their positions so far. On Tuesday, Republican Sen. Joni Ernst of Iowa told Insider that she was keeping an "open mind" about the bill.

Here are the Republican senators who have come out in support of the amended bill:

• Susan Collins of Maine
• Rob Portman of Ohio
• Thom Tillis of North Carolina
• Mitt Romney of Utah

This post will be updated as the legislation moves through the legislative process.