Senate Republicans waved the white flag last week on their months-long effort to repeal the Affordable Care Act. But by the looks of his Twitter account, President Trump really wants Congress to keep trying.

Unless the Republican Senators are total quitters, Repeal & Replace is not dead! Demand another vote before voting on any other bill!

— Donald J. Trump (@realDonaldTrump) July 29, 2017

There are a few ways Congress could restart its efforts to repeal the ACA, or Obamacare, but most would exact a serious cost on Republicans’ agenda, their popularity and the health insurance markets.

Don’t give up Republican Senators, the World is watching: Repeal & Replace…and go to 51 votes (nuke option), get Cross State Lines & more.

— Donald J. Trump (@realDonaldTrump) July 30, 2017

But since the president wants to know, here are four ways Obamacare repeal could rise from the dead, ranked from least to most likely.

4. The Trump administration lets parts of Obamacare collapse.

Thus forcing formerly reluctant Republicans back to the negotiating table. Trump could do this two ways, both of which he hinted at in tweets recently:

If a new HealthCare Bill is not approved quickly, BAILOUTS for Insurance Companies and BAILOUTS for Members of Congress will end very soon!

— Donald J. Trump (@realDonaldTrump) July 29, 2017

If ObamaCare is hurting people, & it is, why shouldn’t it hurt the insurance companies & why should Congress not be paying what public pays?

— Donald J. Trump (@realDonaldTrump) July 31, 2017

Let’s take these threats one by one.

Trump could stop issuing federal government payments to insurance companies. Insurers rely on these payments to make up for lower-income people, who pay less for health insurance under Obamacare.

But: Most health-policy experts agree that if these subsidies are taken away without a change in how much lower-income people pay for their health insurance, insurance markets would implode, forcing insurance companies to leave Obamacare exchanges, thus causing Obamacare itself to implode.

This option is basically a giant game of chicken with Republicans in Congress, and the health-insurance market is the one that could take the fallout.

Another option is that Trump could stop paying subsidies for members of Congress and most of their staff. Obamacare shifted Congress off its federal government health plan and onto the Obamacare exchanges. It looked politically dense for members of Congress to pass an unpopular law they were exempt from. But lawmakers aren’t entirely on their own. Just like employees in the private sector get contributions from their employers to buy health insurance, the federal government pays for…