Washington (CNN) Former Vice President Joe Biden is the frontrunner to be the 2020 Democratic presidential nominee. Which is why his campaign's purposeful lowering of expectations on Tuesday won't work.

"Do we think we have to win Iowa? No," said one Biden campaign aide speaking to reporters . "Do we want to win Iowa? Yes, we do. We think we're going to win; we know it's going to be a dogfight. The same thing is true in New Hampshire."

Uh ... well, no.

Here's the thing: When you are the frontrunner, you are expected to win. Everywhere. Otherwise, you aren't the frontrunner anymore. That's how it works.

Remember back in 2008 when Rudy Giuliani, who polling suggested was the frontrunner for the nomination, based his entire campaign strategy on skipping Iowa in order to definitely win in New Hampshire? And how when New Hampshire started to go south on Giuliani, how Florida became the new New Hampshire for him? And how Giuliani never won a single primary or caucus and, relatedly, didn't get elected president?

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