DES MOINES — As Elizabeth Warren and Amy Klobuchar escalated their attacks on Pete Buttigieg in Thursday night’s Democratic debate, and Mr. Buttigieg forcefully pushed back, a crucial if unspoken fact was driving the political combat: All three candidates are trying to knock each other out in the Iowa caucuses, where they need strong finishes to stay viable in the 2020 race.
Unlike Joe Biden and Bernie Sanders, who don’t need to win Iowa to springboard to the next primary contests, Mr. Buttigieg and Ms. Klobuchar have virtually no path to the nomination without exceeding expectations in Iowa with a victory or at minimum a top-three result. Ms. Warren, who has fallen out of first place in Iowa polls but has a strong organization there, is looking for a momentum-reviving rebound — or at least a way to halt Mr. Buttigieg’s rise there.
Rarely are presidential primary debates as clarifying about the political stakes for candidates as Thursday’s Democratic face-off, where Mr. Biden largely held back and Mr. Sanders trained most of his fire at the former vice president — both content to let the other three candidates duel and perhaps diminish one another with attacks over experience, fund-raising, free college and “wine caves.”
“Warren has to win Iowa, Pete has to win Iowa, Amy has to pull as close to the top as possible to leverage her way into the top tier,” said David Axelrod, the longtime political strategist who helped Barack Obama win the Iowa caucuses in 2008 and build momentum against Hillary Clinton in their long nomination fight.
With few recent polls in Iowa or new ones likely over the holidays, the Democratic primary race here and in the other early states is entering a murky phase where the ups and downs and the broader contours of the competition will be difficult to divine. For Ms. Warren, Mr. Buttigieg and Ms. Klobuchar, Thursday’s debate was a major chance to try to shift the dynamics in the race by undercutting rivals and underscoring their own strengths and abilities, in hopes of leaving impressions that will last into early January.
Mr. Buttigieg, the mayor of South Bend, Ind. wanted to show that he was prepared to take jabs from rivals and fight back, for instance, as he demonstrated with Ms. Warren, the Massachusetts senator, and Ms. Klobuchar, the Minnesota senator.
“I’ll throw an elbow when I have to,” Mr. Buttigieg told a town hall audience Friday in Walnut, Calif. “That’s starting to happen in the debates a little bit and I don’t mind defending myself.”
Ms. Warren, who was assailed by rivals in the October debate and did not aggressively counterpunch, and slid in the polls afterward, showed a fighting side and pointedly portrayed Mr. Buttigieg as an ally of rich donors, an argument that could help her with Iowa liberals.
But some Iowa Democrats were not certain if it would be enough.
“One of Warren’s objectives would have to be to win back those who indicated interest — if not support for her — maybe six weeks to three months ago, when her ascent was not only halted but, according to most polls, reversed,” said Kurt Meyer, the Democratic chairman in Mitchell County. “I’m uncertain if her performance last night was sufficient to allow her to conclude, ‘mission accomplished.’”
Ms. Klobuchar, who is running in fifth place in Iowa, also tried to take on Mr. Buttigieg, a fellow moderate, and create momentum heading into 2020 as she continues introducing herself to a national audience.
“I do think Klobuchar helped herself a lot last night with her emphasis on her experience in government and her results-oriented approach,” said John Grennan, the Democratic chairman in Iowa’s Poweshiek County. “She and Buttigieg have been trying to ‘out-Midwest’ each other for a while, and Klobuchar has done a good job presenting herself as someone who understands life in this part of the country.”
The unusually spirited debate featured sharp exchanges and extraordinarily pointed personal attacks, in a clear sign that the presidential race is accelerating toward a combative pinnacle — and that every candidate has now firmly trained their sights on Iowa.
Ms. Warren and Mr. Buttigieg, who are fighting for supremacy here, testily traded barbs over wealth and transparency, issues that both candidates have increasingly put front and center at campaign stops here.
Ms. Klobuchar, whose expectations are high in Iowa despite consistently ranking behind the top tier in polls, hit Mr. Buttigieg on his key Achilles’ heel, his experience, playing directly to Iowans’ concerns that the two-term mayor is too green to hold America’s top job.
Mr. Biden, prone to wobbly debate performances that have unnerved even the Iowans prone to back him, had his strongest showing yet. Mr. Sanders was Mr. Sanders, displaying the same unabashed obstinacy that has kept him at or near the top of the polls in Iowa and in other critical early states.
On Friday morning in Los Angeles, Mr. Biden congratulated himself for staying out of the sniping between the others onstage.
“I do worry about this notion that the Democratic candidates spend a lot of time attacking one another. I’ve tried not to do that,” Mr. Biden said. “What I’ve tried to do is focus on why I believe I’m most qualified to beat Donald Trump.”
With just over six weeks until the first-in-the nation Iowa caucuses on Feb. 3, the seven candidates on the debate stage appeared intent on resetting the scene and jostling a fluid race that so far has produced no outright front-runner.
But in a practical sense, the debate reflected the race: It was a five-way competition between Mr. Buttigieg, Ms. Warren, Mr. Biden and Mr. Sanders who are lumped into the top tier, with Ms. Klobuchar chasing at their heels. Under the new criteria released on Friday by the Democratic National Committee, only those five have qualified for the January debate, which will be held in Des Moines. All except Mr. Sanders will be in Iowa this weekend, getting in a last dash before the slower holiday week.
All are aware that where they finish in Iowa will almost certainly determine the trajectory of their candidacies going forward. The idiosyncratic caucus system dictates that candidates must register at least 15 percent support at a caucus site to collect that caucus site’s share of state delegates, to say nothing of the media attention garnered by a top finish that could catapult them into the next states to vote: New Hampshire, Nevada and South Carolina.
Mr. Buttigieg’s aides and allies don’t think the attacks from Ms. Warren on fund-raising and Ms. Klobuchar on experience will damage the South Bend mayor. Much of his rise was powered by his big-money fund-raising and for many of his supporters, his lack of experience is a plus, not a mark against his candidacy.
“Pete is best on his feet and he showed that last night because every time he got attacked he attacked back and he was not wounded at all,” said Jon Soltz, a founder of VoteVets, the progressive veterans organization that backs Mr. Buttigieg. “He goes into Iowa like he was the night before, the front-runner. Nothing changed.”
Mr. Buttigieg spent Friday morning meeting with a dozen municipal officials and community activists in South Gate, Calif., a heavily Latino Los Angeles suburb. He didn’t address his debate performance during a 45-minute round table discussion at a recycling plant and left the facility without answering questions from reporters.
But the situation is much different for Mr. Biden and Mr. Sanders. Though neither can shrug off Iowa, and though neither has given any indication that they are doing so, the state is not make-or-break for them. Both are running strong in other key early states: Bolstered by his popularity with black voters, Mr. Biden is well ahead in South Carolina; likewise Mr. Sanders, who has shown strength with Latinos, is polling well in Nevada and California, which votes on Super Tuesday. And a disappointing finish for him in Iowa is unlikely to shake his loyal supporters elsewhere.
Those dynamics mean that the remaining weeks before the caucuses could feature an increasingly intense battle among Ms. Warren, Mr. Buttigieg and Ms. Klobuchar.
The stakes are perhaps highest for Ms. Klobuchar, who has charmed many Iowans but has yet to surge in the state. Part of her strategy in Iowa is to visit all of the state’s 99 counties, a goal she will inch toward meeting this weekend on a 27-county bus tour.
Still, she did her best to break through on Thursday. And among voters and Democratic officials in the state, the consensus was that she succeeded.
Ms. Warren’s whacks at Mr. Buttigieg might have benefited Ms. Klobuchar, too.
“If people start to think Buttigieg needs more experience or is too caught up in money politics, it seems like Klobuchar is an option for those who want a more moderate candidate but who aren’t sold on Joe Biden,” Mr. Grennan, in Poweshiek County, said.
Of course, with less than 50 days to go before the caucuses, it is possible that the debate did little to fundamentally reshape the race.
“I didn’t see anything that will change the minds of committed caucusgoers,” said Dan Callahan, the Democratic chairman in Buchanan County.
Sydney Ember reported from Des Moines and Reid J. Epstein from Walnut, Calif. Katie Glueck contributed reporting from Los Angeles.