While the deal, which replaces NAFTA, is widely seen as a crucial pre-election year win for Trump, Pelosi has long emphasized that passing a new NAFTA goes beyond partisan politics, particularly given Democrats' long history of criticizing the old pact's harm on American workers.

"I know there are those ... who have said 'Why? You shouldn't do this. This gives him a win.' No. We are so far away from the proposal that he put forth that this is a triumph for American workers," Pelosi said at POLITICO's Women Rule Summit. "We are miles and miles from what he put forth. So he has yielded on what this is."

A vote on the U.S.-Mexico-Canada Agreement could come as soon as next week — Dec. 19, some senior Democrats speculated — which would be the day after the House is expected to vote on impeachment.

Pelosi already has said she does not want impeachment to be the last thing members vote on before the holiday recess. The new trade agreement is expected to pass both chambers with broad support, though it's likely the Senate won't take it up until early next year.

The deal gives moderate Democrats a win to tout at home. Moderates — particularly those from districts Trump won in 2016 — have stressed the pact's importance in their districts as they look to defend their seats in next year's election.

Congressional Democrats' top demands appear to have made it into the final version of USMCA, including a provision that allows the U.S to verify that Mexican factories are complying with higher labor standards and penalize them if they do not, according to a fact sheet provided by House Democrats.

Democrats also succeeded in pushing the Trump administration to remove a provision establishing a 10-year protection period for biologic drugs, which opponents say would allow drug companies to keep prices high.

On Tuesday afternoon, U.S. Trade Representative Robert Lighthizer, Canadian Deputy Prime Minister Chrystia Freeland and Mexico's Undersecretary for North America Jesús Seade were in Mexico City for a signing ceremony for the revised deal. Mexican President Andrés Manuel López Obrador, who has been eager to wrap up a deal, was also present.

“All of us together have finally accomplished what we set to do from the outset — a win-win-win agreement,” Freeland said.

The pact also won the backing of the AFL-CIO, the nation's largest labor federation, marking the first time the influential group has endorsed a pact in nearly two decades.

Lighthizer emphasized Tuesday how significant it was to reach a trade agreement with support from the Trump administration, Democrats, major labor unions and the two North American trade partners.

“It’s nothing short of a miracle that we have all come together,” Lighthizer said at the ceremony.

The top trade officials from the three countries acknowledged that the negotiations were difficult and heated at times. Pelosi and Ways and Means Chairman Richard Neal (D-Mass.), who led negotiations with the Trump administration, also indicated that the support was hard won.

“I think we set a world record for hanging up on each other, myself and [Lighthizer],” Neal said.

During her caucus meeting earlier on Tuesday, Pelosi hailed the deal as a victory, according to a person present in the meeting.

"We stayed on this and we ate their lunch," Pelosi told the caucus.

The House Ways and Means Committee is expected to waive its time on mock-ups to send the deal straight to the floor for a vote. Neal said it's likely the deal will be voted on the House floor next week.

"This is a transformative agreement," Neal said. "It's a template, I believe, for future agreements."

Lighthizer, in a statement, agreed that the revised deal "will be the model for American trade deals going forward.”

Senate Majority Leader Mitch McConnell told reporters the upper chamber will not take up the trade deal this month. He said consideration of USMCA will “happen in all likelihood right after” the impeachment trial.

Senate leaders could negotiate an agreement to do both an impeachment trial and USMCA in January.

“A lot of our members are going to want to review it,” said Senate Majority Whip John Thune. “I would not be surprised, even if the House does advance it, we just don’t have the available time to process it before the holidays.”

Senate Finance Chairman Chuck Grassley (R-Iowa) said Tuesday morning that he still wants to hold a mock mark-up within his committee.

Some Republicans were briefed by Lighthizer by phone on Tuesday, and Finance Committee members will receive an in-person briefing on Thursday, Grassley said. Members were also briefed in a call Tuesday morning, he said.

“This is long overdue but very welcome news," Grassley said.

Mexico's and Canada’s legislatures must also approve the changes. Mexico is expected to do so in the coming days given that its Senate leaders have already offered support for the revised pact.

A bill to pass USMCA is unlikely to be introduced in Canada's Parliament until late January because its House of Commons will break for the holidays on Friday, according a Canadian government official. The body is scheduled to return on Jan. 27.

Burgess Everett, Heather Caygle, Marianne LeVine and Andy Blatchford contributed to this report.