Critical Research Failure: After slipping away from his Secret Service detail to conduct an affair, former President Douglas says there isn't any danger by asking how many assassination attempts have been made on former presidents. The lead bodyguard responds saying there haven been any. During the 1912 presidential campaign, John Schrank shot former President Teddy Roosevelt prior to him giving a campaign speech. Of course, this being TeddyRoosevelt, he survived and even gave the 90 minute(!) speech before seeking medical attention.
Likewise, the ending (while funny), would be outlawed under Amendment 22 of the US Constitution. No former president can be re-elected to office if they already served a term.