Joe Biden calls possible fourth-place Iowa finish a 'gut punch,' then takes aim at Bernie Sanders, Pete Buttigieg

We still don't know who won Iowa. But, based on the roughly 75% of the data we have, it looks like former Vice President Joe Biden is heading for a disappointing fourth-place finish, behind Pete Buttigieg, Bernie Sanders, and Elizabeth Warren.

That's not great. Biden didn't have to win Iowa, and there are some indications he wasn't fully trying to, but many analysts — and potential donors — said leading into the Iowa caucuses that a fourth-place finish could indicate trouble for Biden's candidacy.

"If he came in fourth, yeah, that could hurt," said Biden donor Bill Freeman. "That's a bad night, no matter how you spin it."

Campaigning in New Hampshire on Tuesday, Biden acknowledged as much.

"I am not going to sugarcoat it, we took a gut punch in Iowa," Biden said, according to the Associated Press. "But look, this isn't the first time in my life I've been knocked down."

Now Biden is having to punch up at other candidates, like Buttigieg and Sanders, for the first time. Until recently, Biden has looked like the unquestioned front-runner. He also needs to convince potential donors not to bail on him at this sign of trouble, telling them that he will bounce back and win South Carolina and Nevada.

On Sanders, Biden said that granting the the Vermont senator the nomination would permanently attach the detrimental "socialist" stigma to the party, something on which President Donald Trump will capitalize, and for which Democratic congressional candidate in purple or blue districts will pay the price.

Biden also said 38-year-old Buttigieg does not have the experience to run the country, as "someone who's never held an office higher than mayor of a town of 100,000 people in Indiana."

Now, Biden must hope for a better showing in Feb. 11's New Hampshire primary.

"I'm not going anywhere," Biden told supporters. "And I'm counting on New Hampshire. We're going to come back."

Despite his Iowa finish, Biden still leads in the national poll, according to RealClearPolitics.