The little tweak that's about to give Trump a big win on health care

House Republicans look to have the votes they need to pass their embattled health care bill. All it took, apparently, was adding a few billion dollars to the bill, to provide cover to moderate lawmakers who had been reluctant to support it.

This latest change, added to the American Health Care Act on Wednesday night with a vote expected fewer than 24 hours later, adds an additional $8 billion to reduce insurance costs for people with preexisting medical conditions. Experts say the funding is still short of what is actually necessary to keep many of those patients from experiencing insurance price spikes if the bill becomes law.

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The provision appears to do enough to satisfy the concerns of a handful of moderates who helped doom the bill in late March, when House leaders had to scrap a planned vote at the last minute. Those moderates, combined with conservatives won over by a separate amendment last week, appear to have given leadership just enough votes to advance the bill out of the House after a months-long slog.

The amendment appears to have won over crucial moderate lawmakers

The latest amendment, pushed by Rep. Fred Upton of Michigan, is intended to fend off accusations that the bill guts Obamacare's protections for people with preexisting conditions.

It is co-sponsored by three Congress members — Jeff Denham of California, David Valadao of California and David Young of Iowa — that the best whip counts had as "lean no" votes. By, presumably, flipping those three votes to "yes," the amendment appears likely to be sufficient to pass the bill in the House, even though it could still lose upward of 20 Republicans.

Upton's role here is crucial. He is the former chair of the House Energy and Commerce Committee and an experienced health care legislator. His defection to "no" on Tuesday suggested that even the revised version of AHCA could be in real trouble.

But after a dramatic trip to the White House on Wednesday, Upton reversed himself and said he would support the bill with his amendment. He later told reporters at the Capitol that he had actually started working on the amendment on Monday night, the day before he publicly announced his opposition.

Upton's conversion — along with that of Missouri Republican Billy Long, another surprising defection earlier this week — seems to have persuaded enough wavering Republicans to come onboard.

The amendment provides more money to lower costs for sick people

The Upton amendment follows from the earlier MacArthur amendment, which wooed conservatives but spooked moderates. That earlier amendment allows states to opt out of the Obamacare rule that prohibited health plans from charging people more for their insurance because of their existing health conditions.

To let insurers opt out of those rules, states must meet certain conditions, such as setting up a "high-risk pool" for people with high medical costs. And people could not be charged more as long as they maintained coverage.

But many experts believed that the funding available under AHCA would not be sufficient to pay for those high-risk pools and prevent major price hikes for the patients with preexisting conditions.

So the Upton amendment pushes even more funding — $8 billion over five years — toward those costs. It is an addition to the $100 billion-plus fund originally included in the bill for states to create programs that reduce insurance costs.

The new money is designated specifically for states that seek a waiver under AHCA and for people in those states who would see higher insurance premiums or out-of-pocket costs because of that waiver.

States could use the money to pay insurers directly to keep costs down, to help people buy insurance in the high-risk pool, or to provide direct subsidies for people to buy their own insurance, Larry Levitt at the Kaiser Family Foundation told me.

But, Levitt said, "There is still nothing in the bill that guarantees people with preexisting conditions will have access to affordable coverage if states waive community rating."

The problem is that the bill neither specifies how the money should be spent nor provides enough of that money, Levitt said. People in states with the AHCA waivers could see "massive premium increases," he told me: "There's no way a reinsurance program or direct subsidies could ever fully offset that for everyone, and states aren't required to do so."

As for high-risk pools, which Vox's Sarah Kliff explained here, Levitt said the funding is "inadequate" and "there are no requirements for what the eligibility, premiums, or benefits in high-risk pools would have to be."

There could still be another fight over funding

Republicans are rushing the bill through the House before the Congressional Budget Office can tell them how much it would cost and how many people it would cover. So moderate Republicans who reluctantly get onboard with AHCA could end up coming back later to ask for more money, Upton said Wednesday.

"Is it enough money? I don't know. That's the question that I asked," Upton told reporters. "I was led to believe that $5 billion would be enough, which is why it's $8 billion, to make sure that in fact it's more than enough."

"If it's not," he said, and CBO comes back with a report that shows that, "then a number of us, including me, will seek more money."

Which, presumably, would require a whole new — and difficult — vote.