If you look at the thread title you'll see it's got a question mark at the end not a full stop.
That means he's not making a statement, (or a point,) he's asking a question.
This is pretty basic stuff. Did you go to school?
Sun 20 Oct, 2019 07:38 am
At first glance, Scenarios 2 and 3 are the only ones which have actually occurred — Nixon in Scenario 2 and Calvin Coolidge and Lyndon Johnson illustrating Scenario 3.
Scenario 4 leaves out a lot of USAmerican history before we had primaries. But someone with better historical knowledge may be able to come up with an example from the 19th Century where a sitting president was abandoned by his party.