Biden dead-ender Joe Scarborough is on guard for anything that might jeopardize his guy's re-election prospects. So when Joe Manchin, the Democrat senator from West Virginia, yesterday floated the possibility of a third-party presidential run, Scarborough was quick to lead the charge against him on today's Morning Joe....with his usual F-words for Trump. When, teasing the news at the top of the show, Mika Brzezinski mentioned Manchin's musings, Scarborough twice interrupted with a skeptical, "come on, man." Scarborough cast Manchin's flirtation in the most negative terms possible: "Do you think he really wants to help a fascist get elected president?...