Oh, I'm well aware it's leaked that far into real life: it's the well-known Single Party Rule, as seen in the former Soviet Bloc, and in most dictatorships, where there's only one candidate on the ballot. And it's justified in exactly the same way: people don't know what's best for them, so the Party must decide on their behalf. It may be good in theory, but it's a corruption magnet.

It's vary rare for senator's to be unable to run for office. Because the things that prevent winning are much wider than the list of things that prevent someone from running.

The most obvious being you can still run while in the middle of a murder trial up to the point where your convicted. But, good luck getting elected.

Yeah, I used senator there, but I was euphemistically referring to term limits, not trying to imply that U.S. senators are subject to them.