COLUMBUS, Ohio >> A bipartisan governor duo is urging Congress to retain the federal health care law’s unpopular individual mandate while seeking to stabilize individual insurance markets as lawmakers work on a long-term replacement.

The recommendation is part of a compromise plan that’s designed to be palatable to both parties. It was endorsed by six other governors.

Ohio Gov. John Kasich, a Republican, and Colorado Gov. John Hickenlooper, a Democrat, shared their plan in a letter to congressional leaders Thursday. They acknowledge that retaining the mandate may be a difficult sell for Congress, which has failed so far to pass a replacement health care bill.

“The current mandate is unpopular, but for the time being it is perhaps the most important incentive for healthy people to enroll in coverage,” they wrote to House and Senate leaders of both parties.

Experts concur that keeping younger, healthier people in the insurance pool protects against costs ballooning out of control.

The penalty and coverage requirement, or individual mandates, were intended to nudge healthy people into the insurance market. They have consistently polled negatively with Americans. In an Associated Press-NORC Center for Public Affairs Research poll conducted in July, 48 percent of those surveyed favored repealing the mandate, while 35 percent opposed repeal.

Kasich and Hickenlooper’s letter was signed by Republican Gov. Brian Sandoval of Nevada; Democratic Govs. Tom Wolf of Pennsylvania, John Bel Edwards of Louisiana, Steve Bullock of Montana and Terry McAuliffe of Virginia; and Alaska Gov. Bill Walker, a one-time Republican no longer affiliated with a political party.

After Republicans’ failure to pass a replacement of President Barack Obama’s health care law, Kasich and Hickenlooper teamed up to push for health care exchanges that would stabilize the market and assure affordability. Both took pains to quash speculation that their collaboration and public appearances suggested a bipartisan presidential ticket was in the making for 2020.

Hickenlooper emphasized Thursday that steadying individual markets is a top — and time-driven — priority. Addressing Medicaid expansion costs and other health care elements can follow, he told reporters in Denver.

“Is this going to fix all that is broken with our health care system? No,” he said. “If we can demonstrate success at stabilizing the individual markets, then we can move to the other parts of health care as well.”

Kasich and Hickenlooper also recommended that President Donald Trump commit to cost-sharing reduction payments to insurers and that Congress fund those offsets at least through 2019. Those payments reimburse insurers for providing low-income people with legally required reductions on copays and deductibles. If Trump follows through on threats to pull the plug, premiums would jump about 20 percent.

Kasich said the proposal satisfies the concerns of all parties studying the health care law.

“If you want to keep what you have, you can,” the Ohio governor said Thursday. “We’ve stabilized everything up front, but then over time, we open up the doors to innovation and individual plans, within guardrails.”

The governors support creating a temporary stability fund that states could tap to reduce premiums and limit losses; continuing to fund educational outreach and enrollment efforts under the Affordable Care Act; exempting insurers that agree to cover underserved counties from the federal health insurance tax; and supporting states’ efforts to find creative solutions for covering the uninsured.

The governors said states can pursue lots of options without federal assistance, but in some cases they are “constrained by federal law and regulation from being truly innovative.”

Kasich and Hickenlooper are expected to be in Washington next week to testify on their proposal. But congressional action on even a modest compromise is expected to be difficult following years of harsh partisan battling over the Republican drive to dismantle the health care law.