With 25 of its members prepared to oppose the House GOP’s plan to repeal and replace Obamacare on Thursday, the House Freedom Caucus says it has the votes needed to block the bill from advancing out of the House.

But Republican leaders in the lower chamber have entered into 11th hour negotiations with conservatives and centrist Republicans in an effort to gain their support for the bill.

The House is expected to vote on the health care plan Thursday, and efforts to sway Republicans to switch their votes in favor of the bill are coming down to the wire. But as the White House continued its charm offensive Wednesday, it didn’t appear the number of lawmakers opposed to the bill was moving at all, which put its future in jeopardy.

According to Alyssa Farah, spokeswoman for the House Freedom Caucus, 25 of the group’s members will vote against the bill, and the conservative caucus encouraged GOP leaders to “start over.”

Rep. Mark Meadows, R-N.C., chairman of the Freedom Caucus, reaffirmed his intent to vote against the bill on Twitter.

In addition to members of the Freedom Caucus, a number of centrist Republicans have come out against the bill as well.

Rep. Charlie Dent, R-Pa., chairman of the Tuesday Group, said late Wednesday he believed the GOP’s health care bill will cause Americans to lose coverage and premiums to rise, particularly for low-income and elderly Americans.

“I hope that the House can step back from this vote and arbitrary deadline to focus on getting health care reform done right to ensure that American families have access to affordable health care,” Dent said in a statement.

Republican Reps. Leonard Lance of New Jersey and Ileana Ros-Lehtinen of Florida also both say they plan to oppose the bill.

They were joined by Rep. Frank LoBiondo, R-N.J., who announced his opposition to the bill earlier Wednesday.

“Simply put, this bill does not meet the standards of what was promised,” he said in a statement. “It is not as good as or better than what we currently have.”

While the Freedom Caucus puts the number of “no” votes at 25, Rep. Thomas Massie, R-Ky., said he has spoken with 29 conservatives who, like him, opposed the bill as of Tuesday evening.

“What are the people saying that are for this on Capitol Hill? Well, they’re trying to tell us it’s a binary decision, that you can either take it or leave it,” he said in an interview with Breitbart Radio. “We think the negotiation starts when one party says no. That’s why we’re going to say no.”

Massie also took to his Twitter account to reiterate his position on the House GOP’s health care bill.

With 237 seats in the House and five vacancies, 22 Republican votes against the legislation would block the plan from advancing to the Senate.

So far, just one Republican who opposed the legislation has switched his vote.

Rep. Lou Barletta, R-Pa., said Tuesday he couldn’t support the GOP’s health care plan because it didn’t include provisions to verify that illegal immigrants wouldn’t get access to the tax credits.

But Barletta announced Wednesday he would be voting “yes” on the legislation, called the American Health Care Act, after meeting with House Speaker Paul Ryan and President Donald Trump on Tuesday night.

“The president gave his full support to legislation I will introduce to deny health care tax credits to illegal immigrants, and the speaker promised to bring the bill to the House floor for a vote,” Barletta said in a statement Wednesday. “Because my concerns were met, I will vote for the bill with the understanding that my bill will receive full consideration on the House floor next month.”

Despite the strong opposition from the Freedom Caucus, the White House seemed confident the bill would pass the lower chamber.

“This count keeps getting stronger for us,” White House press secretary Sean Spicer told reporters today.

Ryan, too, seemed confident the health care proposal would pass and Thursday’s scheduled vote would continue as planned.

“We feel pretty good,” he told Fox News on Wednesday. “We know we feel good at the end of the day here because members promised we would repeal and replace this disastrous and collapsing law.”

“We’re talking to our members,” the Wisconsin Republican continued. “We’re not losing votes.”

The House Rules Committee took up the bill Wednesday morning and, at the time of publication, continued to debate the legislation.

Conservatives continue to take issue with the bill because of the impact it will have on the cost of premiums.

An analysis of the bill from the Congressional Budget Office found that the proposal would cause premiums to rise 15 to 20 percent in 2018 and 2019.

The lawmakers believe Obamacare’s essential health benefits requirements, a list of services insurance plans are required to cover without copayments, need to be repealed for premiums to come down in price.

Conservatives appear to have allies in White House officials and Trump himself, who said he would call on the Senate to include a repeal of the essential health benefits requirements when it takes up the House bill, according to reports.

White House budget director Mick Mulvaney, a former Freedom Caucus member, is also working with Meadows to eliminate the essential health benefits requirements, according to Politico.

While the conservatives are pushing Republicans to include a repeal of the essential health benefits requirements and other insurance regulations in their health care bill, leaders have dug in their heels and warn that an inclusion of those provisions wouldn’t pass muster in the Senate.

In an interview with the Washington Examiner, though, Sen. Mike Lee, R-Utah, said the Senate parliamentarian, Elizabeth MacDonough, told him Republicans could push harder to repeal the insurance regulations through the reconciliation process.

“What I understood her to be saying is that there’s no reason why an Obamacare repeal bill necessarily could not have provisions repealing the health insurance regulations,” Lee told the Washington Examiner.

GOP leaders attempted to gin up support for the bill from conservative and centrist Republicans on Monday when they released changes to the health care plan.

The proposal repealed Obamacare’s taxes in 2017 instead of 2018, and made further modifications to the Medicaid expansion, including a freeze of the expansion in 2020. The plan also changed the tax credits for low-income Americans.

But the changes weren’t enough to sway the lawmakers, who still are pushing for further negotiations.

This article has been updated.