Sen. Elizabeth Warren speaks at a town hall with members of the American Federation of Teachers (AFT), in Philadelphia, PA, on May 13, 2019.
The deal, called the United States-Mexico-Canada Agreement, or USMCA, has earned the support of the country’s largest federation of unions, the AFL-CIO.
Like Sanders, Warren is staking her electoral appeal on the populist wing of the Democratic Party and is seeking union support.
Sanders has said he would not support USMCA after calling its improvements over NAFTA “modest.”
But her vote could indicate how she would treat USMCA if she were to win the White House.