President Donald Trump REUTERS/Yuri Gripas Senate Republicans came out 20 hours of debate with a stunning failure in their efforts to overhaul the US healthcare system, leaving President Donald Trump's agenda in tatters and the party with few clear options moving forward on healthcare.

From Tuesday to early Friday morning, the Senate voted on four new plans to repeal and/or replace the Affordable Care Act (three serious, one not-so-serious). All four were unsuccessful, including Friday morning's dramatic 2 a.m. vote that failed when Sen. John McCain cast his ballot against the measure.

The failure left Senate Majority Leader Mitch McConnell with no clear path forward. The Senate has been grappling for weeks with healthcare overhaul, running through different versions of legislation before settling on the more modest attempt with the aim of moving to a conference with the House of Representatives.

Even so, it's not the end of the road for the healthcare debate.

"This isn’t the end for Repeal and Replace," Cowen analyst Rick Weissenstein said on Friday. "After seven years of railing against the ACA, GOP lawmakers can’t just abandon the quest."

Here are the three groups that will shape what happens next

The Trump administration. Following the vote Friday morning, President Donald Trump tweeted that Republicans should "let ObamaCare implode, then deal." The Department of Health and Human Services, which oversees the provisions of the Affordable Care Act, could choose not to enforce key parts, which could lead to the law's dissolution.

Following the vote Friday morning, President Donald Trump tweeted that Republicans should "let ObamaCare implode, then deal." The Department of Health and Human Services, which oversees the provisions of the Affordable Care Act, could choose not to enforce key parts, which could lead to the law's dissolution. The House of Representatives. Rep. Mark Meadows of North Carolina, the head of the conservative House Freedom Caucus, expressed interest on Friday in creating a new bill that could help the Senate get to 51 votes.

Rep. Mark Meadows of North Carolina, the head of the conservative House Freedom Caucus, expressed interest on Friday in creating a new bill that could help the Senate get to 51 votes. The Senate. The chamber, according to Weissenstein, is the best poised to keep the Obamacare exchanges alive in a bipartisan way. Already, there's interest from Republican Sen. Lamar Alexander of Tennessee and Democratic Sen. Patty Murray of Washington to work together across the aisle.

Of the three, the Trump administration's actions could inflict the most immediate damage on the ACA, Cynthia Cox, associate director at the Kaiser Family Foundation, told Business Insider. That could be through a decision to stop funding cost-sharing-reduction payments, which help offset costs for insurers, not enforcing the individual mandate, or not doing outreach to inform Americans about their health insurance options.

What a new plan might look like

Going forward, the plan to repeal and replace the ACA might be less about sweeping changes and more about incremental tweaks.

"While it is hard to see a path forward for a comprehensive bill, the GOP is likely to try to attach discrete provisions aimed at defunding parts of the bill or unwinding some of the ACA’s insurance or benefit mandates are likely," Weissenstein said.

And there's a chance that Medicaid is safe from huge cuts. Both the House and the Senate bill would have made drastic cuts to Medicaid, the government program that covers 74 million low-income Americans. Even the "skinny" bill that was the Senate's final vote on Friday morning didn't make any major changes to Medicaid. The changes to Medicaid were the sticking point for many Republican senators who had concerns about the bill going into the vote.

But, Cox said, the fact that Medicaid cuts were in both plans suggests that there will continue to be a desire to change the program. One Medicaid program in particular, the Children's Health Insurance Program, is coming up for a reauthorization vote in September, which could leave some room for Republicans to make some changes.