House Majority Leader Kevin McCarthy told a closed-door meeting of House Republicans Tuesday that "now is the time" to repeal Obamacare and that they should be prepared to vote Wednesday or Thursday on the party’s health-care bill.

Representative Dennis Ross of Florida, a senior member of the House vote-counting team, said they are about "five votes away" from the number needed to pass the bill.

But a significant number of moderates remain opposed to the measure. A Bloomberg News count found at least 21 members opposed to the latest version. Republicans can only afford to lose 22 votes and guarantee passage.

Perhaps the most significant defection yet came Tuesday, when Fred Upton of Michigan told a local radio station he would vote against the current bill. Until last year, Upton chaired the Energy and Commerce Committee, which has jurisdiction over much of health-care policy, and has been a staunch supporter of Obamacare repeal.

"I told the leadership I cannot support the bill with this provision in it," he said about changes made to requirements about covering people with pre-existing conditions. "It’s not going to get my ‘yes’ vote the way it is."

As of Monday night, Ross said that even the Republican vote-counting team isn’t entirely on board with backing the revised health-care measure, adding that as many as seven of its members hadn’t yet committed to doing so.

“The longer we wait, the more it’s going to fester,” he said.

‘Pray’ for vote

House Speaker Paul Ryan told his conference Tuesday to "pray" as they try to wrangle the remaining holdouts, Ross said. "This is who we are. This will define us," Ryan told them.

"And McCarthy said look, this will define us. It’s no longer about what we should do or how we should do it. Now is the time to do it," said Ross, quoting the No. 2 House Republican.

“We’re just a handful of votes away," House Freedom Caucus Chairman Mark Meadows of North Carolina said Tuesday.

Meadows said he didn’t think there would be additional changes to the measure.

"There’s always those prospects, but at this point you have to figure out whether you’re going to gain or lose votes based on that," he said. "That will be a hard calculation right now."

Several Republicans, including Representative Brian Mast of Florida, say they’re still undecided.

One problem is that recent changes made to the bill to win over conservative holdouts have alienated some GOP moderates.

Under an amendment to the Republican plan, states could let insurers charge older customers more than the original bill allowed -- at least five times more than younger ones, beginning in 2018. States could also allow insurers to charge higher premiums for people with pre-existing conditions who have had a gap in coverage of at least 63 days in the prior year.

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