In a letter organized by the anti-abortion group Democrats for Life and set to be sent Friday, the group of Christians calls on the Democratic Party to rescind its platform’s support for ending restrictions on federal funding for abortion. That language was added to the party’s 2016 platform, to the frustration of anti-abortion Democrats. Last year, Joe Biden, the Democrat’s presumptive presidential nominee, shifted his position to back an end to restrictions on government funding for abortion.

“We call upon you to recognize the inviolable human dignity of the child, before and after birth,” the group wrote in its letter to the Democratic platform committee, shared in advance with The Associated Press. “We urge you to reject a litmus test on pro-life people of faith seeking office in the Democratic Party.”

Among the signatories of the letter are the Rev. Gabriel Salguero, president of the National Latino Evangelical Coalition and a member of former President Barack Obama’s faith-based advisory council; and John DeBerry, a longtime Tennessee state representative and pastor who was recently removed from the Democratic primary ballot due in part to votes against the party’s position.

Democrats for Life Executive Director Kristen Day said that her group had sent a letter opposing the Democratic platform’s 2016 inclusion of language backing the repeal of limits on federal funding for abortion that drew far fewer signatories. This week’s letter, which includes registered Democrats as well as independents, is “a much bigger effort,” she said.

Day also warned that the addition of another position Biden has backed — codification of the Supreme Court’s Roe v. Wade ruling — would alienate anti-abortion religious voters.

Biden is “a little bit ahead” of where Hillary Clinton was in 2016 in terms of faith-based voter outreach, Day said, but the prospect that the Democratic platform would back codification of Roe “would just massively damage relationships with religious voters who don’t necessarily want to see that.”

While Democrats have shifted leftward on abortion in recent years, there’s some evidence that abortion opponents are still open to supporting the party. Minnesota Democratic Sen. Amy Klobuchar, despite her strong abortion-rights voting record, won unlikely praise from some abortion critics in February for saying that anti-abortion Democrats “are part of our party.”

Day recalled Obama’s work toward “common ground” on abortion, as the former president put it in 2008, and noted that the Biden campaign has hired a faith adviser who worked on Obama’s reelection bid.

“It’s hugely important for the campaign and Vice President Biden to understand the importance of this vote,” Day said of anti-abortion Democrats who may be motivated by their faith. “It shouldn’t be taken for granted.”

A draft Democratic platform released this week will be voted on by mail before the party’s mostly-virtual convention, which is set to start Aug. 17.