During an election, has a U.S. political party ever nominated a alternative candidate to be its frontrunner over an incumbent President of that same party? | AskHistorians Archive Observer

During an election, has a U.S. political party ever nominated a alternative candidate to be its frontrunner over an incumbent President of that same party?

by TheButchman101

Like, let's say for example the Republican Party were to nominate Roosevelt over Taft in the 1912 election. But has it ever actually happened?

PlusGoody

Yes. Lyndon Johnson in 1968 and Truman in 1952 each dropped out fearing they would be denied renomination. Andrew Johnson in 1868 was far too unpopular even to seek the Republican nomination.