My admiration for Jonah can sometimes be mistaken for a small moon. And he makes a better case for a John McCain-Sam Nunn ticket than I expected.

But the odds against it are approximately 3,720 to 1 (I know, I know, never tell Jonah the odds). The reason is simple, and it’s the same reason we won’t see McCain-Lieberman or any other McCain-Conservative Democrat ticket. Asking Republican voters to put a Democrat – even a conservative one – a heartbeat away from the presidency for a 71 year old who has fought cancer is just a bridge too far.

It’s entirely possible that Lieberman or Nunn may end up in high level positions in a McCain administration. Secretary of State Lieberman, Secretary of Defense Nunn — very possible. White House Press Secretary Zell Miller challenging reporters to duels? Would love to see it. But McCain’s running mate has to be someone the GOP base is comfortable with as president. Lieberman and Nunn, even Evan Bayh types some days — they’re all swell guys. But Republicans won’t vote for them to be President if, God forbid, something happens to McCain.

UPDATE: A couple readers note, “Hey, I’d vote for a McCain-Zell Miller ticket, but in this case, Zell would reassure conservatives.”