House Speaker Paul Ryan, left, and U.S. Rep. Rob Wittman appear together in Virginia in 2012 when Ryan was Mitt Romney’s vice presidential running mate. (Peter Cihelka/AP)

Three of Virginia’s seven Republican members of Congress have come out against House Speaker Paul D. Ryan’s plan to revise the Affordable Care Act — and the other four have yet to take a position.

The dissent, from two hard-line conservatives and one moderate, illustrates the challenge House leaders face in pushing a proposal that the Congressional Budget Office said would reduce the deficit but also leave 24 million more Americans uninsured.

For weeks, Reps. Dave Brat and Thomas Garrett, both members of the Freedom Caucus, have warned that Ryan’s plan would not go far enough to roll back former president Barack Obama’s health-care law.

Then on Monday, Rep. Rob Wittman announced that he, too, opposes the plan, saying that “it is clear that this bill is not consistent with the repeal and replace principles for which I stand.”

The move was unexpected because Wittman has a moderate voting record, and, without the support of mainstream members like him, experts say, the bill will not pass in its current form.

“Wittman represents the traditional Mid-Atlantic Republican. He’s not a tea partyer, he’s not Freedom Caucus Republican. He is a legislator,” said David Wasserman, who is House editor at the nonpartisan Cook Political Report.

Through a spokesman, Wittman declined interview requests. Messages of thanks flooded his social-media accounts.

The rest of the state’s Republican congressional delegation has not responded to requests about their positions on Ryan’s plan: Reps. Bob Goodlatte, H. Morgan Griffith, Barbara Comstock and Scott W. Taylor. The only Republican in Maryland's delegation, Rep. Andy Harris, said in a radio interview Friday that he opposes the bill in its current form. Democratic members of Congress from Maryland and Virginia want to defeat the plan.

Republican plans to revise the Affordable Care Act present a political minefield for members such as Comstock, who represents a Northern Virginia district where Democratic nominee Hillary Clinton had a 10-point edge over Republican Donald Trump in November.

“The legislation is a work in progress, and we continue to talk with constituents, medical professionals, and other stakeholders on their concerns and needed reforms,” Comstock spokesman Jeff Marschner said in a statement.

Goodlatte, the senior Republican in the delegation and chairman of the House Judiciary Committee, said in a message to constituents last week that he was still reviewing Ryan’s plan “to make sure it’s a better way forward for Virginians than our current course.”

Griffith, in his weekly newsletter to constituents on Monday, said he expected the bill to change before it reaches the floor and plans to offer an amendment requiring “able-bodied” Medicaid recipients without young or disabled children to work or be retrained.

In an interview Tuesday, Taylor said he was undecided but leaning toward supporting the bill “because this is what I campaigned on and leadership is not about getting 100 percent of what you want.”

The CBO predicts premiums would increase up to 20 percent in the first year under Ryan’s plan, called the American Health Care Act, but decrease by 2026.

Wittman did not explain which provisions of the plan he rejects, but he maintains that the Affordable Care Act should be repealed. He has said he would only favor a plan that preserves Medicare and Medicaid and does not grow government.

“I do not think this bill will do what is necessary for the short- and long-term best interests of Virginians, and therefore, I must oppose it,” he said.

“I do believe that we can enact meaningful health-care reforms that put the patient and health-care provider back at the center of our health-care system, but this bill is not the right answer,” he added.

If Wittman, who was first elected to Congress in a 2007 special election, decides to run for higher office, his early opposition to Ryan’s American Health Care Act could distinguish him from other Virginia Republicans.

In 2016, Wittman was building a campaign for Virginia governor and eyeing a run for the Senate if Clinton had won the White House and installed Sen. Tim Kaine as her vice president. Instead, Kaine stayed put, and Wittman dropped out of the governor’s race to focus on Congress.

He was named chairman of the House Armed Services subcommittee on sea power and projection forces, which oversees the U.S. Navy fleet. Wittman joined Trump this month at the Newport News shipyard, which builds the nation’s aircraft carriers, and both men have said they want to increase military spending.

Republicans say Wittman is a potential contender to challenge Kaine in the 2018 midterm elections.

The congressman’s sprawling Republican district means he must appease independent voters in Prince William County who favored Clinton and die-hard conservatives in the suburbs outside Richmond.

“He’s caught between two Republican worlds,” Wasserman said, “and two kinds of voters who view this legislation with skepticism for very different reasons.”