Ms. Dannenfelser was one of several socially conservative women who signed a letter in January 2016 urging Iowans to vote for anyone else in the state’s caucuses, saying that they were “disgusted” by Mr. Trump’s treatment of women and that they believed “he cannot be trusted” on the issue of abortion.
To win the favor of anti-abortion conservatives, Mr. Trump committed himself to their agenda in a way no previous Republican presidential nominee had. He put out a list of specific candidates he was considering for the Supreme Court, including some who had expressed doubts about abortion rights. And two months before the election, when the Susan B. Anthony List asked him to sign a commitment that he would nominate only “pro-life” justices and slash funding for Planned Parenthood, Mr. Trump agreed.
Filling Justice Ginsburg’s seat, Ms. Dannenfelser said, “is the fulfillment of his No. 1 obligation.”
In evangelical and social conservative circles, an early consensus was emerging that Mr. Trump’s nominee would have to be a woman whose conservative convictions were equal to Justice Ginsburg’s devotion to liberal jurisprudence. Privately, the first name immediately floated among some conservative activists who are close to the White House was Amy Coney Barrett, a judge on the United States Court of Appeals for the Seventh Circuit.
But given Ms. Barrett’s conservative Roman Catholic beliefs, which Democrats pressed her on during her confirmation in 2017, and the concern she has expressed about abortion, her nomination could fail to win votes from some moderate Republican senators — not to mention the fierce resistance it would draw from Democrats and liberal outside groups that have vowed multimillion-dollar campaigns of their own.
While it is impossible to say whether Mr. Trump or Mr. Biden would benefit more from a raging national debate over the future of the Supreme Court, Democrats are showing a growing interest in the issue that party leaders said was encouraging. “I think we are highly motivated about just making sure that vacancy is protected and preserved for the next president,” Representative Alexandria Ocasio-Cortez of New York said in an interview on Saturday.
The prospect of a fight with Democrats over a nominee whom social conservatives view as one of their own — and someone they believe was unfairly targeted for her faith during her confirmation — is something that conservative activists said would energize their voters. But any delay by Republicans, or the selection of a different nominee who is not seen as conservative enough, could deflate that enthusiasm, said Terry Schilling, executive director of the American Principles Project, a group that opposes abortion and gay and transgender rights.