The GOP’s intense antipathy towards unions has always been a potential point of vulnerability for Donald Trump. He needs union votes to win in the swing states in 2020; anything that emphasizes the battle between capital and labor isn’t going to help him, as Scott Walker would be happy to tell you.
On the Democratic side, expect to see all of the candidates lined up to support the union. Don’t be surprised to see Bernie Sanders on a picket line, and he may well have company.
It’s a no-lose situation for the Democrats, even if it emphatically isn’t for the UAW.