“Since Herbert Hoover...”
Since Herbert Hoover, Nixon was challenged in the primary and won reelection. Truman was challenged in 1948 (although this was when the conventions still mattered, before things were fully decided during the primaries) and won reelection. And FDR withstood a challenge by his own vice-president prior to the 1940 election. Conservative Democrats as well as conservative Republicans were deeply worried about FDR flouting the George Washington precedent, and with the economy still not responding, the packing of the Supreme Court, and doubts about the New Deal the challenge was very serious. But FDR was a master politician and was reelected.
So, there is precedent for a sitting president to withstand challenges from within his own party and still be reelected.
I’m foggy about 1972. Who challenged Nixon in the GOP primaries??
What happened to change that? How I long for the days when the big states (like CA) put up favorite son candidates and the roll calls went on all night at the conventions. Constituencies traded votes in smoke filled rooms (we can do without that) and you had to wait until it was all done to find out who the nominees would be. That was really fun for the viewer.
I've been watching (or listening before TV came to my town) the conventions since I was a little girl. I remember hearing parts of the Truman convention on the radio and watched both the Stevenson and the Eisenhower conventions, as well as the Kennedy and Nixon conventions on TV.
As a college kid, my husband had the good fortune of knowing the British Counsel General in Chicago in 1956, and he was given press passes to both the Dem and the Republican Conventions. He was able to get into those smoke filled rooms and watched the pols working behind the scenes. It's not even fun any more. Everyone knows who the nominees will be before they ever start.
Back then, the economy wasn’t as bad as it is now. It’s always the economy that determines who will and will not be president.