WASHINGTON — Congress on Thursday gave final approval to President Trump’s revised North American Free Trade Agreement handing the president his second trade victory of the week as House lawmakers prepared to read aloud charges of high crimes and misdemeanors on the Senate floor.
The 89 to 10 vote in the Senate on implementing legislation for the revised United States-Mexico-Canada Agreement will send the measure to Mr. Trump, who is expected to sign it next week.
The bipartisan vote in support of the trade deal offered a striking contrast to the other big congressional initiative underway: Mr. Trump’s impeachment trial.
Within an hour of senators approving the measure, the seven impeachment managers were set to begin the ceremonial process of presenting the impeachment articles on the Senate floor.
The unusual show of bipartisan agreement came just one day after Mr. Trump signed a long-awaited trade deal with China, giving the president two trade wins in a single week.
Yet the lasting legacy of his presidency may be the competing narrative of a president who has achieved big economic wins while facing accusations of misdeeds while in office. Voters will now have to choose between a president who has lived up to his populist campaign promises to rip up and replace old trade deals with one who is accused of pressuring Ukraine by withholding financial aid to boost his re-election campaign.
A core group of House Democrats, in communication with their Senate counterparts, spent months negotiating new language that ultimately strengthened labor, environmental, pharmaceutical and enforcement provisions. The length of those negotiations pushed the House vote to December, less than 24 hours after the chamber voted to impeach Mr. Trump for high crimes and misdemeanors.
Lawmakers initially suggested that a Senate vote on the pact would be delayed until after the trial, which will begin in earnest on Tuesday and in effect halt all legislative work in the Senate. But when Speaker Nancy Pelosi of California decided to delay sending the articles of impeachment to the upper chamber, senators seized the opportunity to start the procedural maneuvers for the trade pact.
“Our farmers and ranchers expect us to move on this,” Senator Joni Ernst, Republican of Iowa and a prominent advocate for the deal’s passage, said at a news conference on Tuesday.
“Folks back home, they don’t care what’s going on in this bubble surrounding impeachment. They just simply want to know are we doing the work that’s important to them,” she said.
Within nine days, six Senate committees had given the implementing legislation seals of approval, allowing for the vote to occur Thursday morning before the impeachment trial formally began.
“Undaunted by those who set to throw him out of office since day one, President Trump forges ahead for the good of the American people,” Senator Charles E. Grassley, Republican of Iowa and chairman of the Senate Finance Committee, said. “Passage of U.S.M.C.A. is better late than never.”
The bipartisan support for the deal came at a moment when partisan politics have stymied most legislative efforts. In part because of the Democratic stamp on the pact’s terms, Democrats joined Republicans in voting for the deal — including opponents of the original North American Free Trade Agreement and others typically adverse to trade pacts.
“I never thought I’d be voting for a trade agreement during my Senate tenure that I wrote a big part of,” said Senator Sherrod Brown, Democrat of Ohio, who cast his first vote for a trade agreement in a quarter century after labor enforcement language that he and Senator Ron Wyden, Democrat of Oregon, crafted was included in the final agreement.
In 1993, NAFTA passed the Senate on a 61 to 38 vote, and the deal has since been criticized by lawmakers across Capitol Hill for enabling the flow of American jobs to Mexico. A substantial part of the new agreement is dedicated to updating that original text, adding revised guidelines for food safety, e-commerce and online data flows, as well as anti-corruption provisions.
But there are significant changes in the deal negotiated by Mr. Trump’s trade staff and Democrats, including higher thresholds for how much of a car must be made in North America in order to avoid tariffs. It rolls back a special system of arbitration for corporations that has drawn bipartisan condemnation, and also includes additional provisions designed to help identify and prevent labor violations, particularly in Mexico.
Support from a number of prominent labor voices, including the AFL-CIO’s first endorsement of a trade agreement in 18 years, helped firm up the support of Democrats like Mr. Brown, Mr. Wyden and Senator Elizabeth Warren of Massachusetts, a contender for the Democratic presidential nomination.
The most ardent Republican critic of the deal was Senator Patrick J. Toomey of Pennsylvania, who on Wednesday railed against it as “a badly flawed agreement, an agreement that restricts trade rather than expanding trade.” A majority of Democratic opposition was rooted in the deal’s lack of climate change provisions, with Senators Kamala Harris of California, Sheldon Whitehouse of Rhode Island and Chuck Schumer of New York among those voting against the pact.
“When it comes to climate change, the agreement still contains many of the same flaws of the original NAFTA, which I voted against,” Mr. Schumer said in a statement on Thursday.
Ms. Harris has expressed similar concerns, saying in a statement earlier this week that “by not addressing climate change, the U.S.M.C.A. fails to meet the crises of this moment.”