The main national body of the Teamsters union may have declined to endorse a candidate for the 2024 presidential election, but that hasn't stopped local units from doing so.

Jim Hoffa accused the union’s current president, Sean O’Brien, of "a failure of leadership," saying he boosted Trump’s campaign with a non-endorsement.

The Teamsters broke with the union tradition of backing Democrats on Wednesday. Here's a look at how it is different from other major unions.