WASHINGTON — As they take up the campaign to replace the Affordable Care Act, Senate Republicans face a critical choice between cutting taxes or preserving health coverage for millions of Americans, two competing demands that may yet derail the GOP push to roll back the 2010 health care law.

House Republicans, who passed their own ObamaCare repeal measure last week, skirted the dilemma by cutting both taxes and coverage.

Their bill — embraced by President Donald Trump — slashed hundreds of billions of dollars in taxes, a key goal of GOP leaders and the White House as they seek to set the stage for a larger tax overhaul later this year.

At the same time, the House legislation cut more than $1 trillion in health care assistance to low- and moderate-income Americans, a retrenchment the nonpartisan Congressional Budget Office estimates would nearly double the ranks of the uninsured over the next decade to more than 50 million.

In the Senate, coverage losses on that scale are unacceptable to many rank-and-file Republicans whose states have seen major coverage gains under ObamaCare. That makes the preservation of benefits one of the biggest challenges confronting Senate Majority Leader Mitch McConnell, R-Ky., and other GOP leaders.

“Coverage matters,” Sen. Bill Cassidy, R-La., said Tuesday on MSNBC’s “Morning Joe” program, noting the importance of preserving Medicaid spending in the current law. “To someone (who) is lower-income, you’re going to need those dollars to cover that person.”

Yet moderating cuts to Medicaid and other government health programs without driving up budget deficits could force Republican senators to also dial back the tax cuts that many in the GOP want.

“It’s not that complicated. If you want to use money for tax reform, you can’t have it for health coverage,” said Gail Wilensky, a veteran Republican health policy expert who ran the Medicare and Medicaid programs under President George H.W. Bush. “You can’t do both.”

McConnell has convened a group of GOP senators — all of whom originally were white men — to develop ObamaCare replacement legislation, though the panel largely excludes Republican lawmakers who are most concerned about coverage, including Cassidy.

The tax cuts in the House Republican health care bill total more than $600 billion over the next decade, according to the Congressional Budget Office.