House Democratic leaders have begun hedging their bets on holding a vote Saturday on Democrats' proposal healthcare overhaul, saying that the bill could be delayed because of Republican maneuvering and a dearth of votes from moderate Democrats.

The signal -- sent by House Majority Leader Steny Hoyer (D-MD) on a conference call with reporters Friday, comes in addition to a comment by Speaker Nancy Pelosi (D-CA) who, when asked if she had the votes for her healthcare overhaul Thursday, said, "We will."

Hoyer said Democrats are "very close" to securing the 218 votes needed to pass the bill.

Analysts say some Democrats may be thinking twice after the defeat of two Democratic gubernatorial candidates in Maine and New Jersey, worrying that association with the liberal wing of the party may cost them their seats.

Hoyer, however, said he still expects a vote Saturday night.

"Assuming...that we follow the schedule we have set, my expectation is we will finish debate on the bill, on the Republican substitute, and will be voting on the rule and the substitute and the bill, and will have final 7 to 8 o'clock tomorrow night," Hoyer said.

But if Republicans try to delay the bill, its passage could fall until Monday or Tuesday.

"Clearly, things happen, and delaying tactics can be employed," Hoyer added. "All I've done is make sure everybody understands that we're going to complete this effort."

Some Democrats are still withholding support, hung up on issues of paying for abortions and providing healthcare for immigrants.

"We are working on those now to make sure we have a construct that will facilitate the passage of the bill," he told reporters. "We're very close."

Obama is expected to seek support for the bill during appearances on Capitol Hill Friday.