You think things in Washington were ugly before? Just watch.

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

There are two key ways the President of the U.S. could undermine the law: asking his agencies not to enforce the individual mandate created under Obamacare; and stopping funds for subsidies that help insurers offset health-care costs for low-income Americans. Both moves could further disrupt the Affordable Care Act’s individual markets and eventually lead to higher premiums -- and angry constituents.
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Where does this leave Trump’s implosion threat? One of the first steps the president could take would be to stop the monthly payments to insurers known as cost-sharing-reduction subsidies. The administration last made a payment about a week ago for the previous 30 days, but hasn’t made a long-term commitment. Trump has called the subsidies a “bailout” for insurance companies in the past.
“We are still considering our options,” Ninio Fetalvo, a spokesman for Trump, said in an e-mail.
America’s Health Insurance Plans, a lobby group for the industry, said premiums would rise by about 20 percent if the payments aren’t made.

Premiums were expected to rise by 10%-30% anyway. What this is suggesting is 20% increase in addition. Plus more than 2 in 5 insurers would abandon Obamacare without CSRs.
Trump could effectively gut Obamacare out of spite.
Would he do that? Would he hurt tens of millions of Americans just so that he could "win"?

It's with no little irony that Sam Brownback left Kansas, the state he decimated with a tax plan that destroyed the economy, to join the Trump Administration this week.
Because of the failure on Obamacare repeal, Republicans are set for a massive tax cut plan.

“The stakes really have been doubled now for tax reform,” said Steve Moore, who was a top economic adviser to Trump during the campaign. “They absolutely can’t lose. They can’t accept failure on that, or it will be a completely wasted first year of the presidency.”

Amazingly, for the upper-middle class, nearly 20% of households, taxes would actually rise under Trump's plan in order to pay for tax cuts for the 1%. Even Fox News admits it.
While tax cuts are near and dear to Republicans, it's nowhere near a slam dunk.