Throughout the hundreds of speeches the top-polling Democratic candidates have given in Iowa, there’s one common theme: Each claims they have forged a path to win the caucuses, then the nomination and, ultimately, the presidency.

Now, the candidates have less than a month before the first-in-the-nation caucuses on Feb. 3 to turn those sketched-out paths into reality.

Each candidate's path is different. Top-polling contenders in Iowa — former Vice President Joe Biden, former South Bend, Indiana, Mayor Pete Buttigieg and U.S. Sens. Bernie Sanders and Elizabeth Warren — hope for an outright win on caucus night. Lower-polling candidates seek a surge to one of the top spots, which could vault them into contention.

Beyond winning, caucus night is also about beating expectations, said Lara Henderson, who was the Iowa state director for U.S. Sen. Kirsten Gillibrand’s presidential bid, which ended in August. An unexpectedly strong finish in second or third can propel a candidate onward, while a narrow victory for a candidate who was expected to win big can raise doubts.

“I feel like the expectations have been so shifting on each person at every given moment in this race that it’s going to be an entirely different set of expectations when we get to caucus night,” Henderson said.

► More in this series: 14 moments that have shaped the 2020 Iowa caucuses (so far)

One of the tests for the campaigns will be seeing who has built the volunteer infrastructure that can take advantage of caucusgoers who decide late, said Margaret Jarosz, who was caucus director for former U.S. Rep. Beto O’Rourke’s presidential campaign, which ended in early November.

“I think you’re about to see who’s actually built an organization that can turn that funnel into winning on caucus night,” she said.

Meanwhile, candidates like U.S. Sens. Cory Booker and Amy Klobuchar and businessman Andrew Yang are arguing they can still have breakout moments in Iowa to propel them to the nomination.

Jarosz praised Yang for bringing new people into the caucus process and said Klobuchar could take advantage of the bump she’s seen from strong debate performances.

“She’s starting to take off,” Jarosz said of Klobuchar. “And I think her staff is trained really well, and I think if they can capitalize on it, they could be a force coming down the stretch.”

Ultimately, Jarosz said, the race is likely to be determined by organizing fundamentals — lining up precinct captains, identifying supporters and getting them to turn out on caucus night.

Why are the Iowa Caucuses first? The history of the first-in-the-nation caucus The Iowa caucuses are not first because they're important, they're important because they're first. Former Des Moines Register opinion editor Kathie Obradovich gives a brief history lesson on the Iowa caucus. Kelsey Kremer, kkremer@dmreg.com

“I feel like that’s kind of the beauty of this race is that it literally comes down to organizing and who has the strongest organizing team,” she said.

Here’s a look at how the top-polling candidates have charted their paths through Iowa over the last year and what political observers and the campaigns themselves say they need to do to win:

Joe Biden: Lean on ability to beat Trump

A brief look a Joe Biden's path through Iowa Former Vice President Joe Biden attended 80 public events in Iowa in 2019. Kelsey Kremer, kkremer@dmreg.com

Biden was the front-runner in the presidential field before he joined the race, with a December 2018 Des Moines Register/CNN/Mediacom Iowa Poll pegging his support at 32%. He held the lead through two more Iowa Polls, but Warren overtook him in September, and Buttigieg overtook her in November.

Now, Biden is waging a hotly contested battle among the top-tier candidates in Iowa.

The former vice president tied Sanders for third place in the November poll, with 15% support. Warren was in second place.

Biden's pitch remains the same as when he joined the race last April: He’s the candidate who can defeat Republican President Donald Trump, rebuild the middle class and restore “the soul of America.”

Former Vice President Joe Biden speaks to a woman in the crowd after giving a speech in the South Ballroom inside the Iowa State University Memorial Union on Wednesday, Dec. 4, 2019, in Ames. Kelsey Kremer/The Register

Biden had a shaky performance in the first Democratic presidential primary debate in June, when U.S. Sen. Kamala Harris sharply criticized his record on busing, and he made some misstatements on the campaign trail over the summer. But Biden said he wasn’t concerned the gaffes would impact his ability to take on Trump.

While Trump’s impeachment dominated national news in the fall, the proceedings had little impact on the campaign trail in Iowa. Most candidates, including Biden, weren’t being asked about the issue, despite the fact that Trump was impeached, in part, for asking the president of Ukraine to investigate Biden and his son Hunter Biden, who served on the board of a gas company in that country.

In late November, Biden got a boost with the endorsement of former Iowa Gov. and U.S. Secretary of Agriculture Tom Vilsack and former Iowa first lady Christie Vilsack. He capitalized on the Vilsacks’ endorsements by launching an eight-day bus tour of Iowa with them in tow. The “No Malarkey” tour has been Biden’s longest campaign swing through the state to date, taking him across the state from west to east, through 18 counties.

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The tour also saw Biden lean heavily into his core message: That he’s the most experienced candidate in the field and can restore America’s standing on the global stage. The tour allowed him to bring that message to rural Iowa, where his campaign hopes to outperform the competition among the kind of older, more moderate Iowa caucusgoers who, the campaign believes, are most likely to show up on caucus night.

Jarosz, who worked with the O'Rourke campaign, said Iowans' familiarity with Biden has given him a firm base of supporters who know how the caucus process works and who will show up on Feb. 3.

"I think Biden kind of falls (on) the same wavelength as Bernie, where he just has some hard-core people here that are going to work for him and know how to get people into his corner and know how a caucus works," she said.

Former Vice President Joe Biden, Democratic presidential candidate, walks into is event on Friday, Dec. 27, 2019, at the Williamsburg High School in Williamsburg, Iowa. Kelsey Kremer/The Register

While Biden himself has said he's "not running to come in third or fourth or fifth or anything like that," his campaign officials have said that Iowa is not a must-win state for the vice president.

While Biden's polling numbers have lagged in Iowa, he has led most polls in both Nevada and South Carolina. Political observers have said he, unlikely many other candidates, may be able to bounce back from a respectable but not first-place showing in the first-in-the-nation caucus state.

“When he came into it, the expectation was it was his to lose,” Henderson said. “... Nobody is saying that anymore. They’re saying he needs to do well. It’s an entirely different conversation.”

—Stephen Gruber-Miller

Voter guide: Don’t have a lot of time? Find FAQs on the key issues and where the candidates stand and more to make your vote matter.

Pete Buttigieg: Capitalize on surge

A brief look at Pete Buttigieg's path through Iowa Former South Bend, Indiana Mayor Pete Buttigieg attend 99 public events in Iowa in 2019. Kelsey Kremer, kkremer@dmreg.com

The first time Buttigieg introduced himself to Iowans as a presidential contender, he was at an Ames coffee shop surrounded by a small group of people. The person who introduced Buttigieg on that February day mispronounced his name. A loud coffee grinder interrupted the 37-year-old's talk.

Nearly a year later, Buttigieg is in contention to win the Democratic Iowa caucus.

Buttigieg reflected on the trajectory of his campaign during a town hall in Indianola at the end of 2019.

“Since a year ago, we started this effort with four people, no money, an office about the size of this stage that I’m standing on, and a few big ideas,” he said. “And one year later, here we are, with over 700,000 contributors, with a team of hundreds — including a fantastic group on the ground here in Iowa … gone from nobody being able to say my name to none other than the president of the United States helping people figure out how to pronounce it.”

South Bend Indiana Mayor and 2020 Democratic presidential candidate Pete Buttigieg marches with supporters before the Iowa Democratic Party's 2019 Liberty and Justice Dinner on Friday, Nov. 1, 2019 in Des Moines. Brian Powers/The Register

The change was first clear in April, when he came to Iowa just days after formally declaring a bid for the Democratic nomination for president. Large crowds gathered to hear Buttigieg speak across the state.

Buttigieg highlighted the importance of a new generation of leadership to address issues like climate change, gun violence and wage inequities. His health care policy, which would give Americans a choice on whether to eventually eliminate private insurance coverage, resonated with some Iowans who were unsure about a government-run “Medicare for All” system.

Throughout the summer and fall, Buttigieg’s ground game in Iowa continued to grow, and in September, his campaign announced plans to open 20 field offices in 20 days. His campaign staff now numbers more than 100, ranking as one of the largest operations in the state.

Buttigieg has capitalized on strong fundraising to put his resources to the best use, said Sue Dvorsky, a former Iowa Democratic Party chair who endorsed Harris before the California senator dropped out of the race.

“He spent that money smart. He bought up ad time and he bought up field organizers. And he can pay for both,” she said.

Pete Buttigieg, mayor of South Bend, Ind., signs an autograph after his campaign rally at Lyons Four Square Park on Tuesday, Sep. 24, 2019, in Clinton. Kelsey Kremer/The Register

In November, Buttigieg led the Des Moines Register/CNN/Mediacom Iowa Poll for the first time, with 25% support. The rise has brought more scrutiny to his candidacy, particularly his lack of support with African-American voters, his high-dollar fundraisers and his time spent working in the private sector.

In the final weeks before the caucuses, Buttigieg is focusing on a message of unity. As he did during his well-received Liberty and Justice Celebration speech, Buttigieg is making a pitch that he can best unite both progressives and moderates.

Henderson said Buttigieg, along with Warren, has one of the strongest organizations in Iowa, and he'll need to show he can out-organize the competition to take advantage of his surge in support.

"Right now, people are expecting Pete to do very, very well," she said. "That expectation could shift a little bit, but underperforming that expectation is going to hurt."

► Previously: When have recent caucus winners surged in the Iowa Poll?

► More: A look back at the history of Iowa Caucus results, from 1972 to 2016

— Barbara Rodriguez

Bernie Sanders: Expand on 2016 base

A brief look at Bernie Sanders' path through Iowa U.S. Sen. Bernie Sanders attended 117 public events in Iowa in 2019. Kelsey Kremer, kkremer@dmreg.com

In the last caucus cycle, in early 2015, U.S. Sen. Bernie Sanders entered the first-in-the-nation race with little name recognition and single-digit support in polls among likely Democratic caucusgoers.

In 2019, he didn’t have to introduce himself.

Between the two campaigns, he fought Hillary Clinton to a near tie in the 2016 Iowa caucuses. While he didn't secure the nomination, he worked to turn his campaign into a national movement. The nonprofit advocacy group Our Revolution spun out of his campaign to push progressive policies and politicians. Like-minded people successfully ran for Congress and state offices across the country.

Sanders points with pride to what he calls the “grassroots activism” that grew out of his 2016 Iowa caucus campaign. That campaign was described as being like an airplane that was built while in the air. This time, he has built from an established foundation.

Show caption Hide caption Vermont Senator and 2020 Democratic presidential candidate Bernie Sanders laughs at a response as he talks to kids at the Union County Democrats booth during... Vermont Senator and 2020 Democratic presidential candidate Bernie Sanders laughs at a response as he talks to kids at the Union County Democrats booth during the Union County fair on Saturday, July 20, 2019, in Afton. Brian Powers/The Register

"At this point (in the 2016 cycle), it was perceived we were behind, but not all that far behind,” Sanders said in a late December interview. “In comparing 2016 to now, what I would say without the slightest hesitation is we have a much stronger organization staff, we have a stronger grassroots network. So I'm feeling very, very good."

His longstanding championing of progressive values has earned him solid support in Iowa. When the state’s largest progressive group, Iowa Citizens for Community Improvement, held a presidential forum in September, the announcer needed to say only “from Vermont” before the cheers broke out.

But as he planned another Iowa trip shortly after that event, Sanders had a heart attack. It sidelined the 78-year-old senator — with a habit for endurance-testing swings through Iowa and other states — for two weeks. He canceled the tour of Iowa and postponed a $1.3 million ad buy in the state.

Then the campaign came roaring back to life. First, it claimed the largest crowd anywhere this cycle when 26,000 people gathered in New York City to see Sanders accept the endorsement of U.S. Rep. Alexandria Ocasio-Cortez. Then, it claimed the largest crowd at that point in Iowa, more than 2,400 people, when Ocasio-Cortez joined Sanders at a rally in Council Bluffs.

The November Iowa Poll showed Sanders’ supporters to be the most enthusiastic and locked in of the field. Now, the campaign is working to mobilize that base into an army of outreach.

Sanders, who tied Biden at 15% in the November poll, has not faced the same scrutiny as the other top-polling candidates, Henderson said.

“Right now, he’s kind of flying under the radar despite being in that top four,” she said.

U.S. Sen. Bernie Sanders, D-Vt., talks with people in the crowd after a town hall event on Monday, Sep. 23, 2019, at the Clinton Masonic Center in Clinton. Kelsey Kremer/The Register

Dvorsky, who supported Hillary Clinton in 2016, said Sanders' success that year was built on the strength of his ardent supporters, as well as a contingent of anti-Clinton caucusgoers. With a larger field of candidates, support is split, she said, and Sanders' test this year will be whether he can expand beyond his base.

"That will be a story, too, whatever place he comes in," she said.

As a repeat candidate, Sanders also has had more time than his competitors to make sure his volunteers are trained and ready for caucus night, said Jarosz, who worked for Sanders in 2016.

"You can’t ignore the fact that he has two cycles," she said.

— Nick Coltrain

Candidates on the issues: Find out how the 2020 presidential candidates plan to tackle healthcare, climate change, gun violence and more.

Elizabeth Warren: Ace final organizing test

A brief look at Elizabeth Warren's path through Iowa U.S. Sen. Elizabeth Warren attended 82 public events in Iowa in 2019. Kelsey Kremer, kkremer@dmreg.com

Warren was first out of the gate to hire up key staffers, launching what would soon be regarded as the state’s premier organizing team.

“They started collecting cards about 20 minutes after she hired them, and they haven’t lost any of them,” Dvorsky said, referring to "commit to caucus" cards supporters fill out to pledge their backing.

Warren’s first Iowa events in January 2019 took her through central and western Iowa, where she unveiled her signature, methodical “selfie” line. As she laid out proposal after proposal through the spring and summer, her “I have a plan for that” line began to resonate.

Warren’s approach remained slow but steady: She traveled to Iowa no more than a twice a month through much of the year.

By the time of the Democratic Wing Ding dinner in August, Warren was met with a celebrity’s welcome by a raucous team that lined the streets for hours. As she emerged from her RV — which was plastered with the words “Honk If You Like Big, Structural Change” — she hugged her screaming volunteers and posed for pictures.

The next day, she was met with one of the biggest crowds at the Des Moines Register’s Political Soapbox, easily drawing thousands of Iowa State fairgoers. It was the moment her 2% wealth tax became a rallying cry for her campaign as supporters in the crowd began chanting “Two cents!”

Isabelle Webber, of Marion, poses for a selfie with Elizabeth Warren, candidate for president, outside of the Iowa Democratic Party's hall of fame event on Sunday, June 9, 2019, in Cedar Rapids. Kelsey Kremer/The Register

Warren again showed off her organizing strength at the Polk County Steak Fry, where her staffers opted out of the typical sign wars, instead setting up an “organizing HQ,” where volunteers got tips for canvassing the crowd and signing up supporters.

Having strong data is essential for identifying potential supporters and making sure they turn out on caucus night, Jarosz said.

"I think Warren has been doing that," she said, while also praising Sanders' effort.

The weekend of the Steak Fry, Warren rose to the top of the September Iowa Poll, when 22% said she was their first choice.

But front-runner status drew heightened attention. Rivals attacked her calls for big, structural change, including her Medicare for All plan, as too costly or unlikely to gain passage.

In the November poll, her support slipped to 16% — second in a tight pack with Sanders and Biden, who were tied with each other just 1 percentage point behind her. Buttigieg had surged to a commanding lead.

Since then, Warren has changed up her campaign style in Iowa as she looks to jump-start her support, giving more time for questions and personal interaction with potential caucusgoers. Those exchanges show Iowans a more empathetic side of her, beyond her reputation as a policy wonk.

► More in this series: These are the 14 moments that have shaped the 2020 Iowa caucuses (so far)

Iowa politicos say they’re watching to see whether Warren’s much-heralded ground game is enough to secure her a victory on caucus night. Though other candidates appear to have surpassed her in sheer enthusiasm, Iowa tends to reward those with superior relationships on the ground.

On caucus night, attendees will have a chance to vote for their first-choice candidates. But candidates will be dropped from contention if they don't get at least 15% support from the people in that caucus location. That means field organizers and precinct captains in every caucus location who can win over supporters will be critical before Iowans vote again. Warren may have that organizational edge.

Warren, like Sanders, has also invested heavily on college campuses. Those densely progressive strongholds helped boost Sanders in 2016, bringing him to within a fraction of a percentage point of caucus winner Hillary Clinton. If Warren can wrest away enough of that support, it could give her an edge.

Show caption Hide caption Members of the crowd gathered to listen to U.S. Sen. Elizabeth Warren, D-Mass., speak outside of the Iowa Memorial Union step up to meet her and... Members of the crowd gathered to listen to U.S. Sen. Elizabeth Warren, D-Mass., speak outside of the Iowa Memorial Union step up to meet her and take a selfie after a presidential campaign rally on Thursday, Sept. 19, 2019 on the University of Iowa campus in Iowa City. Kelsey Kremer/The Register

Warren has also spent considerable time in eastern Iowa counties that voted twice for Democrat Barack Obama before flipping in favor of Trump. Others, particularly Biden, are competing aggressively for support there, too. If Warren’s organize-everywhere approach pays off, she could stifle Biden’s appeal in the state’s more rural counties, as well.

— Kim Norvell

Stephen Gruber-Miller covers the Iowa Statehouse and politics for the Register. He can be reached by email at sgrubermil@registermedia.com or by phone at 515-284-8169. Follow him on Twitter at @sgrubermiller.

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