Washington, DC CNN  — 

Senate Democrats privately signaled concerns Thursday about pushing ahead with a vote on the sweeping voting rights and ethics bill that had become a top priority for Democratic leaders and progressive outside groups – at least without first making changes.

The concerns, aired in a private Democratic meeting on Capitol Hill, followed confirmation Wednesday that West Virginia Sen. Joe Manchin – a crucial vote in Democrats’ narrow majority – would not back S1, known as the For the People Act, which Democrats see as a way to blunt Republican state-level efforts to restrict voting access. Manchin, who was not at Thursday’s meeting because he’s traveling with first lady Jill Biden in his home state, suggested instead that the path forward lies in pushing legislation that would have a narrower scope.

One source familiar with the discussion at Thursday’s meeting said that lawmakers signaled that while they had signed onto S1, they still had changes they wanted to make – some of them significant. Sen. Mark Warner, a Democrat from Virginia, told the caucus that some things in the bill still needed to be adapted and that it was one thing to have a bill that was seen as a messaging bill and another thing to vote on the legislation as it is.

A spokesman for Warner declined to comment.

The major voting rights package would mandate 15 days of early voting, allow same-day voter registration and limit states’ ability to curb mail-in voting and the use of ballot boxes. It also rewrites federal campaign finance rules, sets out new ethics requirements for the president and seeks to end partisan gerrymandering.

It wasn’t clear from the meeting, according to the source, what the next step for the bill would be after the Rules Committee deadlocked along partisan lines on passing the bill out of committee earlier this week, revealing the tough path ahead for the Democratic legislation.

While Senate Majority Leader Chuck Schumer could still bring the bill to the floor, the vote in committee was a reminder that the legislation will not have the 60 votes needed to pass and has no Republican support.

Manchin had previously expressed reservations about moving forward with a far-reaching measure without bipartisan support.

His suggestion for legislation that can move forward – the John Lewis Voting Rights Act – is a bill far less sweeping. But it would bring back major pieces of the 1965 Voting Rights Act, including a provision that require states to consult with the federal government before making major changes to their voting rules.

Manchin’s support of that bill was first reported by ABC News.

In recent weeks, Manchin has had conversations with Democratic colleagues Rep. Jim Clyburn and Sen. Raphael Warnock, both of whom have fought to pass the For the People’s Act.

On Tuesday, Republicans, led by Senate Minority Leader Mitch McConnell, repeatedly took aim at the 800-plus-page legislation with a raft of amendments that forced Democrats to cast a series of controversial votes.

This story has been updated with additional developments Thursday.