(CNN) It's been almost 140 years since a US president didn't veto something during his time in the White House. If Senate Majority Leader Mitch McConnell keeps blocking for President Donald Trump, then he could be the next. McConnell, for now, controls the Senate floor and as long as the Senate Republicans carry water for the President, he won't have to veto anything. That said, here's how the veto and veto override process works. In the House, Democrats have 235 seats and Republicans have 199 and there's one vacancy.

Source: CNN January 20, 2019 13:20 UTC