The Democratic Party‘s late-stage candidate swap from President Joe Biden to Vice President Kamala Harris may have opened up new weaknesses in the crucial “blue wall” states despite Harris’s boost in national polling.

The Teamsters Union caused a stir Wednesday by releasing internal polling that found former President Donald Trump leading Harris nearly two-to-one among its members. The union subsequently declined to issue an endorsement, the first time it had not backed the Democratic presidential ticket since 1996.