There is nothing Donald Trump could do that would be egregious enough to get the Republican controlled Senate to vote to remove him from office. Though many Republican senators would possibly be happy to have Mike Pence be president, his ascendancy would leave the vice presidency vacant. That would leave Speaker Of the House Nancy Pelosi next in line to be president. If Pence were to die before a new VP nominee could be confirmed, Pelosi would become president. And there's no guarantee anyone would be confirmed to succeed Pence as vice president. The nomination would have to be approved by both houses of Congress and the Democrat-controlled House would be happy to stonewall until a new VP is chosen by election in 2020.

If the Republicans still controlled both houses of Congress, getting rid of Trump in favor of Pence might be a remote possibility. The order of succession would still be Republican all the way down. But with Democrats in charge of The House and Pelosi currently third in the order of succession, it's simply not going to happen.

Republican senators are willing to put up with anything Trump does or says because having him in office minimizes the chances that an untimely stroke or heart attack might result in a President Pelosi.