It is a very apt analogy, though I don't think Jeb understands exactly why.
For a host of reasons, McCain had little chance in a national election...perhaps he knew that going in, he certainly ran like he knew he could never win.
For entirely different reasons, Jeb is a certain loser. As certain as the sun rises in the east in the morning. He has absolutely no chance whatsoever of winning a national election.
Maybe he sees it too. Maybe not. But EVERYONE else, everywhere, knows it with absolute certainty.