A decadelong bipartisan effort to build a women’s history museum in Washington is nearing the finish line, but a bill to make it happen now has a lot less Democratic support than it did just a month ago.

The House is set to vote Thursday on legislation that would secure a location on the National Mall for the previously approved Smithsonian American Women’s History Museum. Recent GOP revisions, though, prompted scores of Democrats to say they won’t vote for the measure in its current form.

The legislation, authored in February 2025 by Rep. Nicole Malliotakis, R-N.Y., has 231 co-sponsors, including 127 Democrats. At the end of last year, the bill had such strong bipartisan backing that even Republicans had grown frustrated with Speaker Mike Johnson, R-La., for not bringing it to the floor.

But Democratic support for the bill has dwindled in recent weeks as House Democrats say an amended version would give President Donald Trump unilateral control over the museum’s ultimate site and its construction.

The revised bill that’s set to hit the House floor specifies the museum’s site — near the U.S. Holocaust Museum — and adds that the president may designate an “alternative site” within 180 days of the bill’s passing. It would also give the Smithsonian’s Board of Regents the license to “plan, design and construct” the museum’s building, subject to the approval of a set of architectural planning boards consisting of members who were handpicked by Trump.

Those boards would also be tasked with approving a slate of architectural projects Trump has spearheaded during his second term, like the White House ballroom and a triumphal arch.

The Democratic Women’s Caucus announced its formal opposition to the bill Monday after 146 Democrats signed a letter last month asking Johnson to restore the previous version of the bill.

They said that, in addition to giving Trump control over the museum’s site and design, the “eleventh-hour amendment” included language that said only “biological women” could be included in the museum, which they said targeted transgender women and girls and invited arbitrary enforcement. They also took issue with the legislation’s being unpaired from a plan to build a national museum for the American Latino.

Malliotakis said in an interview Wednesday that Democrats were “hiding behind” Trump’s having control to change the museum’s site, arguing that their opposition was rooted solely in the inclusion of a phrase that specified the museum would include only “biological women.”

“The Democrats started pulling out of the bill when an amendment was passed in the [House] Administration Committee that simply added clarification to that — that the museum is restricted to biological women only. I mean, it’s a women’s history museum. The fact that they would pull their support because it says it in the bill that it would only exhibit biological women is ludicrous to me,” Malliotakis said.

She added that she has been working closely with the White House and the Interior Department on the museum’s site and that the location could change only if the currently planned spot proved to be “not buildable.”

Rep. Judy Chu, D-Calif., lambasted the amended bill, saying in a statement that Democrats had worked in “good faith to build bipartisan support” and that Republicans were the ones who added “culture war language.”

“Republicans shattered that bipartisan agreement by handing President Trump unilateral authority over where the Museum will be located, overriding the bipartisan Smithsonian planning process Congress worked on for years, just so Trump can turn it into another one of his personal political projects,” Chu said. “Then they layered on divisive anti-trans culture war language that had nothing to do with the original bipartisan bill.”

Rep. Teresa Leger Fernández of New Mexico, chair of the Democratic Women’s Caucus, called the revised bill an example of Republicans’ being “trans obsessed” and ceding control to Trump.

“It was a simple bill. You kind of ruined it with your trans obsession and your culture wars,” Leger Fernández said.

Johnson weighed in Wednesday, telling reporters that the “biological women” phrase had made Democrats “run for the hills.”

“The Democrats may be OK ceding control of their party to the most radical far-left people in the country, but Republicans are not going to be any party to that. We’re not going to stand for it, and neither are the overwhelming majority of Americans who still believe in common sense,” Johnson said.

The partisan divisions are in sharp contrast to earlier support from lawmakers in both parties, as illustrated by Malliotakis’ using the bill as a cudgel against Johnson in December, when she blamed him for delaying a floor vote as other Republican women openly expressed their frustration with him over a variety of issues. She said in an interview in January that she was given private assurances that Johnson would move the bill along.

The bipartisan goodwill was still publicly on display at an NBC News event last month with Rep. Debbie Dingell, D-Mich., and Malliotakis, who called the museum “critically important” to knowing the story of “amazing women who have come before us, who have helped us build this nation.”

Referring to the actor who played Wonder Woman in the 1970s, Lynda Carter, an advocate for building the museum, Dingell said at the event: “We don’t look at this as Democrats or Republicans or Wonder Woman. We look at it as people in this country should know the history of so many incredible women.”