The new, rewritten North American trade deal - approved by the U.S. House of Representatives on Thursday in an overwhelming 385-41 bipartisan vote.
It comes just a day after a starkly partisan vote by the Democratic-led House to impeach President Donald Trump.
The U.S.-Mexico-Canada Agreement, or USMCA, was first agreed to in September 2018, but was recently altered, after House democrats had refused to hold a vote until provisions were included to protect workers and the environment - among other topics.
The re-negotiated USMCA includes tougher labor and automotive rules than its predecessor, NAFTA.
Trump has blamed NAFTA for the loss of millions of U.S. factory jobs to low-wage Mexico.
In an interview with Reuters, Richard Trumka - president of the powerful AFL-CIO labor union - gave the USMCA his blessing.
(SOUNDBITE) (English) PRESIDENT OF THE MAJOR AFL-CIO LABOR UNION, RICHARD TRUMKA, SAYING: "It's going to take a few years to begin to reverse the bad and the evil that was done by NAFTA, the harm that was done to our economy and to the manufacturing sector in our economy and to other sectors as well.
So it's going to take eight, 10, 12 years, for this process to work through and reverse itself.
But you never get to the end product if you don't start somewhere.
This new agreement will allow us to start that process of healing." USMCA leaves $1.2 trillion in annual U.S.-Mexico-Canada trade flows largely unchanged.
Thursday’s House vote sends the measure to the Senate, but it remains unclear when the Republican-controlled chamber will take it up.
Senate Republican leader Mitch McConnell has said that consideration of the measure would likely follow an impeachment trial in the Senate, expected in January.