If he wins he can still run for president. Lots of senators run for president. He probably wouldn't, he'd be to elated he won anything for one thing, another would be if by some miracle he won it would give him time to get some experience under his belt.
I don't know what that means for all the people who have donated to his presidential campaign. I am not that up on federal election rules or the paperwork required to be filed, I only know it has to be filed and he has to prove it was all spent on his campaign.
Like I stated I haven't seen much of his stuff lately so I haven't seen him explicitly state he has given up running for president. I can only speculate on a number of reasons if he said that as to why. One being maybe the Libertarian Party told him he is not going to be nominated, or two maybe it was just for shit and giggles and he has had all his fun, three his bus did a dive mechanically a while back and it would cost a small fortune to put it back on the road and run it hard like that, four he's burned all his bridges and it's getting harder to get people to run around the country on a bus looking like a well put together team. Like I said that's all speculation but the one I am more prone to go with is he was out having a good time while it lasted.
I don't doubt that.
Thanks for taking the time to answer, and correcting some assumptions I had about the process. The litany of BS already existing combined with this most recent gear shift just seemed weird to me.