CNN  — 

Former Vice President Joe Biden’s central argument in the 2020 campaign is this: President Donald Trump is the real enemy and the most important/only thing that should matter to Democrats is nominating someone who can beat him.

“Everybody knows two things. You have to win, you have to be able to beat Trump and you have to be able to elect Democrats in states we have to win,” Biden said in Manchester, New Hampshire, over the weekend. “You have to be able to win back a United States Senate if you’re going to get anything done.”

But here’s the thing about putting all of your eggs in the “electability” basket. If you don’t win – like, right from the start – then people start to see you as less electable.

Witness Biden’s numbers on the electability question in the latest Quinnipiac University poll, released Monday afternoon.

Roughly 1 in 4 people (27%) said Biden had the best chance of beating Trump as the Democratic nominee in November, while 24% said Bernie Sanders did and 17% named Michael Bloomberg.

Now compare those with a January 28 Q poll, where 44% said Biden was the most electable against Trump as compared with 19% who named Sanders and 9% who chose Bloomberg.

What changed between the two polls? The Iowa caucuses – where Biden finished fourth, and looked less like a winner than a loser. And so, his electability number dropped.

The truth about human nature, and therefore politics, is that people tend to want to be aligned with a winner. And if you don’t look like a winner, they will go to someone who does. Electability, then, is in the eye of the beholder.

The Point: Another poor Biden showing tomorrow in New Hampshire’s primary and the whole “electability” argument will probably disappear entirely. Which is a major problem for his chances.