House Democrats are scrambling to line up the votes needed to push through a $1.85 trillion social safety net, climate and tax bill, as moderate Democrats, spooked by Tuesday’s electoral drubbing, have raised concerns about the cost and details of the rapidly evolving plan.

Late Thursday night, Democratic leaders postponed a vote on the measure to Friday, when they also hoped to clear a Senate-passed $1 trillion bipartisan infrastructure bill for President Joe Biden’s signature. A senior aide who disclosed the update on the condition of anonymity said they were confident they could complete the measures by Friday.

House Speaker Nancy Pelosi of California had previously privately told her top deputies that she had hoped to hold a vote on the social policy bill Thursday night, with the vote on the infrastructure measure Friday morning, according to two people briefed on the discussions.

With Republicans united in opposition, Democrats could afford to lose as few as three votes from their side. Among the biggest issues were the cost and economic effects of the social safety net bill.

A few centrists were also balking at supporting the package — which includes monthly payments to families with children, universal prekindergarten, a four-week paid family and medical leave program, health care subsidies and a broad array of climate change initiatives — before evaluating the fiscal impact of the latest, hastily assembled 2,135-page version of the legislation.

“There is certainly a lack of trust among some of the moderates,” Rep. Henry Cuellar, a conservative Democrat from South Texas, told reporters. “I want to move the ball forward. But I mean, I still want to know, what are the differences?”

Biden made personal calls Thursday, as did Pete Buttigieg, the transportation secretary, who reached out to at least one Democrat facing a tough reelection.

Yet final sticking points continued to crop up throughout the day. Working to appease Democrats who wanted the bill to grant a pathway to citizenship for millions of people living in the country illegally, leaders included a compromise proposal to instead give them work permits and protection from deportation, a status that would eventually allow the immigrants access to some federal benefits.

But some Democrats in swing districts, worried about their party’s deteriorating political fortunes, resisted allowing them access to any benefits, worried that it might be used by Republicans as an election cudgel.