As they try to advance historic trade legislation, GOP leaders are stuck dealing with two of their least favorite groups—House Democrats and the Senate.

With a vote set for Friday, both Republicans and their pro-trade Democratic allies are outwardly confident they have the votes to pass Trade Promotion Authority, a major domestic policy priority for President Obama. The problem now, they say, is as much a procedural one as a political one. And both sides are working to find a solution that won't scuttle the bill's tenuous support in the House—or send it back to the increasingly gridlocked Senate.

At issue is the Trade Adjustment Assistance bill slated to accompany TPA. House leaders from both parties have found a way to pay for the bill without capping Medicare spending, which had been a sticking point for Democrats. But they need to advance that change with a "vehicle" that won't require sending the bill back to the Senate, which would further complicate passage.

An aide to a pro-trade Democratic member described one solution being discussed as a "motion to divide the question" on TAA, enabling the fix to come to the floor without forcing a vote to cut Medicare or sending it back to the Senate.

"We worked together to come up with an alternative, and we did," House Speaker John Boehner told reporters Wednesday, referencing his Tuesday evening meeting with Minority Leader Nancy Pelosi. But he added that the procedural mechanisms are still unsolved.

"How we're going to work through this, the process of how we're going to consider the four different votes, is still up in the air," he said. "If we fix the problem, the offset in the [TAA] bill, and we do it in the first vote, which would be the preferences bill, we believe that solves the problem."

It's expected that TPA and TAA will come to the floor separately, though in the same vote series. Not every Democrat was happy with that plan. "I'd link [TPA] directly with TAA," said Rep. Joseph Crowley. "... If [Republicans] expect bipartisan support for the TPA, we expect that the TAA bill that comes before the House is something that Democrats will support. This is not one that I would support. We've been told that the offset would be fixed before the bill came to the floor, and that hasn't happened. So yeah, I'm frustrated."

Procedure aside, trade supporters remain confident TPA will pass the House. The aide to the pro-trade member said 25 Democrats are currently yes votes, several of whom plan to keep their support a secret until the time comes to vote. Rep. Ron Kind, the New Democrat Coalition chair, who has spearheaded efforts to bring Democrats on board, has been coordinating whip counts with Republicans for two weeks and expects about 200 of their members to vote for TPA. The White House has also mounted an intensive lobbying campaign, dispatching top aides to meet with Democrats on the Hill again Wednesday.

While the aide didn't expect any TAA snafus to bring down TPA, many Democrats have said they can't support the former without major changes. The Congressional Progressive Caucus, which opposes the fast-track legislation, started whipping against the TAA bill, despite it being a Democratic priority, over the cuts.

That's significant because if, as expected, House leadership sets up two separate votes on fast-track and TAA, the latter will likely need Democratic votes to carry it. Republicans are generally opposed to the program, which helps American workers put out of work by foreign trade.

Republican leaders are betting that the change to the TAA offsets will mollify enough Democrats to get both it and the fast-track bill passed and avoid a conference with the Senate. It's not clear yet whether they're right about that. "If people are looking for an excuse to vote no, they can find an excuse," Boehner said.

GOP leaders are cautiously aiming to consider the bill on the floor Friday.

"I think we have a really airtight case to make. We're in our closing arguments. We're comfortable. And that's why we're proceeding," Ways and Means Committee Chairman Paul Ryan said, exiting a morning meeting of House Republicans.

House conservatives, who made an offer last week to vote for the trade deals in exchange for a series of demands, are decrying the procedural changes, however.

"The parliamentary hoops we're jumping through are becoming offensive—constitutionally offensive," Rep. Mick Mulvaney said. "We're supposed to vote on what the Senate sends us. And we are bending the Constitution to almost the point of breaking."

Mulvaney said he is considering voting against the rule governing debate on the House bill, but it is not clear whether his or other conservatives' objections would hold up the process.


Dylan Scott contributed to this article

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