Updated: 1:49 p.m. | House Republican leaders early Wednesday filed a package of trade bills with the Rules Committee, putting the gears in motion for the most anticipated floor showdowns of the legislative session so far.

Though nothing is set in stone, lawmakers who support Trade Promotion Authority are growing increasingly confident they have the votes to bring the measure to the floor on Friday.

The Rules Committee is set to meet Wednesday afternoon to establish parameters for floor debate on a TPA, along with two related bills which would clear the way for President Barack Obama to negotiate a controversial, 12-nation Pacific trade deal.

One of the related bills extends the African Growth and Opportunity Act, an Africa-centered trade deal, and the other focuses on enforcement issues and bolsters U.S. Customs and Border Protection.

Perhaps the most important development of the last several hours is that the TPA is now packaged with a new offset for Trade Adjustment Assistance, which helps American workers displaced by trade agreements succeed elsewhere in the U.S. economy.

Progressives — and plenty of other Democrats, too — were threatening to vote against TAA if it was paid for through sequester cuts to Medicare, as was the original plan. As Democratic and Republican leadership staffs worked to negotiate a different pay-for Tuesday night, the Congressional Progressive Caucus began formally whipping against any measure that included the provision (the caucus is already united in opposition to the overlying TPA).

The TAA offset is now achieved through “strengthening Federal tax compliance laws.” However, progressive House Democrats suggested Wednesday they still aren’t satisfied with the arrangement.

The TPA and TAA are currently lumped into a single bill, with the House expected to bifurcate the measures on the floor. The way all the bills are structured now and with the current understanding of how the votes will be stacked, the plan is for lawmakers to vote first on the same TAA language sent over by the Senate, which still includes cuts to Medicare. Later in the sequence, members would vote for the bill that extends AGOA and establishes trade preferences, which contains language clarifying that TAA should be offset not through Medicare cuts but through strengthened tax compliance laws.

Following the House Democrats’ news conference with anti-TPA advocacy groups outside the Capitol Wednesday morning, Rep. Jan Schakowsky, D-Ill., made it clear this was no “deal” her colleagues would support, as it would still put Democrats on record supporting Medicare cuts, which Republican lawmakers and operatives could in turn use on the campaign trail to punish Democratic candidates.

She added that House Democratic leaders, during that morning’s weekly caucus meeting, were urging members not vote “no” on the TAA bill as currently written in spite of the pay-for clarification elsewhere. House Democratic leadership is still not whipping either way on TPA.

Speaker John A. Boehner, at the GOP leadership news conference taking place simultaneously inside the Capitol, suggested that ideally the first vote in the sequence would be for the language correcting the TAA offset, but he acknowledged that the process for consideration of the four different trade bills was still “up in the air.”

Even holding the vote to extend AGOA first wouldn’t make much of a difference, Schakowsky seemed to indicate.

Ways and Means Ranking Member Sander M. Levin, D-Mich., also took issue in a statement Wednesday afternoon on provisions in the House’s version of the Senate-passed customs bill.

“Anyone who is thinking of supporting TPA must consider the amendments to TPA incorporated in the Customs bill,” said Levin, who is not voting for TPA. “House Republicans are using the Customs bill as a vehicle to further in TPA their rigid ideological agenda. They also strike any form of meaningful action against currency manipulation and weaken trade enforcement provisions.”

Republican leaders and the GOP-led Rules Committee will have to weigh all these factors as they plot next steps.

Elsewhere, Democrats and Republicans are busy lobbying their shrinking number of undecided colleagues to come over to one side or the other.

The news conference in which Schakowsky participated, led by the caucus’s most vocal opponent of TPA, Rep. Rosa DeLauro, D-Conn., featured dozens of Democratic lawmakers pleading with members to vote “no” or, if they’d committed to voting “yes,” change their stance.

“We ask you to reconsider,” DeLauro said, “think carefully about what you’re doing and what this puts in place for the future, we cannot afford it.”

Hasan Solomon, a legislative director with the International Association of Machinists and one of the many representatives of unions and advocacy groups joining lawmakers at the rally, had particularly strong words for pro-TPA Democrats: Vote “yes,” and “you need to start to pack your bags now because we’re going to fast track you out of office.”

Roughly 19 Democrats are committed supporters of TPA, with only a handful of others still playing their cards close to their chests.

Republicans are by and large united on the measure, but conservative hardliners could cause mischief.

On Tuesday night, the House Freedom Caucus met in the basement of Tortilla Coast, the Capitol Hill restaurant where previous conservative brainstorming sessions have taken place.

Roughly 20 members of the HFC huddled for nearly two hours in the private Rio Room discussing trade along with the Export-Import Bank, which is due to expire at the end of the month.

When Rep. Curt Clawson, R-Fla., emerged from the basement, he told CQ Roll Call, “the group is hanging together” on TPA.

Of course, the HFC isn’t entirely united. Reps. Tim Huelskamp of Kansas, Matt Salmon of Arizona, and Tom McClintock of California are all expected to vote in favor of the so-called “fast-track” trade bill.

One Republican in particular is especially certain that everything will work out, and he might be in the best position to quell anxiety: Ways and Means Chairman Paul D. Ryan, R-Wis., who has taken the lead on crafting the House’s version of the trade bills and in counting votes.

Ryan emerged from Wednesday morning’s weekly House GOP conference meeting and expressed confidence in the expected Friday vote on TPA.

“We’re moving because we feel comfortable, and let’s just leave it at that,” Ryan told reporters.

As for the concern over the Senate pay-for, Ryan said Republicans had “no problem whatsoever” in addressing that offset Medicare offset.

“We wanted to accommodate the concern about TAA, and therefore, we dealt with that concern,”he said.

While the TPA vote has been painted as an every-vote-counts, down-to-the-wire situation, Ryan didn’t exactly seem worried. “I think we’re doing well,” he said. “Actually, we’re doing really well.”

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