The positioning and rhetoric shows that Buttigieg betting there is an opportunity for him to pick off voters who might like Biden yet would be happy with a candidate further to the left — just not as far left as Sanders and Warren, taking advantage of the big ideological space between the two senators at one end of the Democratic primary and the former vice president at the other end.

“There's a lot of voters and a lot of caucus-goers who identify as progressives, but aren't as far to the left as Senator Sanders and Senator Warren and wonder how we're going to pay for all of the programs that they keep saying we need to do,” Buttigieg’s Iowa state director, Brendan McPhillips, said on a recent conference call with donors, according to an audio recording obtained by POLITICO. “And Pete is setting himself up as a more electable, viable progressive — I guess, pragmatic progressive, if you will.”

Buttigieg expanded in the interview, saying that just because he’s not lining up with Warren and Sanders doesn’t mean he isn’t putting forward “bold” plans.

“The reason that I've pushed off both candidates running to my left and some of the ideological centrists is that I believe we not only can, but must, be bold and unify at the same time,” Buttigieg said.

In the conference call, McPhillips told the assembled donors that Biden is leading the primary field "in large part due to familiarity. People know who he is,” McPhillips said. “But as the campaign continues people are starting to see some of his flaws, some of his missteps.”

The contrast with Biden makes increasing sense for Buttigieg. The South Bend mayor, believing that his core campaign pitch transcends ideology, is competing in some way with every one of his top rivals ahead of the Iowa caucuses. But Buttigieg also said he believes that he is unlikely to win voters fixated on Medicare for All and the candidates who back it, meaning he needs to peel away support elsewhere to grow in the Democratic primary.

"I think we have to make the case, but I also think that if you have decided that your single criterion for the nominee is you want the left-most candidate, then you've already got your candidate," Buttigieg said. "That's not going to be me."

Evan Bayh, the former Indiana governor and senator who has participated in a campaign event for Biden and is planning on attending a Buttigieg event, said Buttigieg is trying to chart a course through the middle of the primary.

He’s “saying, look, we need to do better because the challenge is greater” than the current system can handle, Bayh said, “but we can't go so far to make it politically suicidal which banning private healthcare would entail. And that's the ground he's trying to find. For lack of a better term, [he's] trying to be a progressive but pragmatic about it."

But Jim Messina, the campaign manager for former President Barack Obama’s 2012 reelection campaign, said drawing distinctions on policy will only take candidates so far with undecided primary voters.

“I am skeptical detailed differences on policy really win large swaths of undecided voters,” Messina wrote in an email. “Democrats are like everyone else, they want to support a candidate who lays out a compelling vision for the future and inspires them. It doesn’t mean policy doesn’t matter, it just this move is unlikely to accomplish the task at hand.”

POLITICO NEWSLETTERS POLITICO Playbook Sign up today to receive the #1-rated newsletter in politics. Sign Up Loading By signing up you agree to receive email newsletters or alerts from POLITICO. You can unsubscribe at any time. This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.

The shift to a contrast campaign comes after Buttigieg spent part of the last Democratic presidential debate admonishing fellow candidates for scuffling over policy — "This reminds everybody what they cannot stand about Washington, scoring points against each other, poking at each other, and telling each other that ‘my plan, your plan...’" Buttigieg said — before Julian Castro cut him off.

But he has since started to draw more contrasts, and in more policy areas than health care. During a recent bus tour through Iowa, Buttigieg said that while he and Warren share many of the same goals, "she's more interested in the fighting part of it. I'm more interested in outcomes."

Warren supporters leapt on the comment, noting her role implementing the Consumer Financial Protection Bureau, but Buttigieg stood by the claim.

"I think my point is that the tone of our campaigns is very different,” he said. “I won't shrink from a fight. I just picked a very big one with this drug policy and I'm prepared to stand for what we believe in and face anyone who's going to challenge that. But I also think it's important to think about what kind of figure America is going to need when the Trump presidency ends.”