Elizabeth Warren’s slow but steady rise in the first-in-the-nation caucus state is as much a result of her robust organizational presence here as it is a response to the Massachusetts senator’s many plans and policies, Iowa experts say.

“You’re seeing a major result of Sen. Warren being here a great deal, hiring a smart team in Iowa and executing a smart campaign operation,” said Matt Paul, a Des Moines operative who ran Hillary Clinton’s 2016 Iowa caucus campaign.

According to the latest Des Moines Register/CNN/Mediacom Iowa Poll, Warren now leads a crowded field of Democratic presidential contenders, displacing former vice president Joe Biden from the top of the poll for the first time this caucus cycle.

Twenty-two percent of likely Democratic caucusgoers say Warren is their first choice for president, compared with 20% for Biden and 11% for U.S. Sen. Bernie Sanders of Vermont. No other candidate reaches double digits.

It’s the first major shakeup in the polling standings, said pollster J. Ann Selzer, president of Selzer & Co., which conducted the poll.

But the results were not surprising, said several Iowa Democrats who have watched Warren build out a team that is widely credited with having the most sophisticated organizational presence in the state.

“If she ends up winning this, one of the factors very well may be that she took the time to recruit top talent and have that talent in place and focused on a plan before announcing,” Paul said. “That continues to pay dividends.”

The same week Warren announced a presidential exploratory committee, she made her first trip to Iowa, announced she had hired four of the state's top Democratic political operatives and then set about quickly building the state’s largest organizing team.

Lara Henderson, who was state director for U.S. Sen. Kirsten Gillibrand’s now-ended Iowa caucus campaign, said that while other candidates have had viral moments or quick bursts of national attention, Warren’s team has excelled at capturing those moments and turning them into on-the-ground support.

“Immediately after (a moment like that happens), you should follow up with everybody saying, ‘Did you see this? What are your thoughts? Let’s discuss,’” she said. “… Anything you can use as an opening to have a personalized conversation with somebody about the election is what you need. So the ability to do that, to get people personally invested on your staff on the ground as well as your candidate, is how you’re going to make a lasting impact.”

Henderson said those relationships are key, and Warren's team creates them effectively.

“Half these people decide who they’re supporting because of their relationship with the staff. You can’t overlook that fact,” she said. “But the way you create that relationship is finding an opening through a viral moment or a way for them to pay attention to your candidate. And the ‘having a plan’ thing — every time they release a plan they talk about it and say, ‘Hey, I want to chat with you about this plan.’ They’re able to find a way to personalize it and find the issues that matter to each individual caucusgoer. It’s not a small thing. It’s making caucusgoers feel like they’re personally speaking to them.”

At the Polk County Steak Fry Saturday, Warren’s team used the massive event as an organizing opportunity, in contrast to the many sign wars, marching bands and rallies other campaigns arranged. Warren's team turned their rally site outside the venue into an “organizing HQ,” where their staff trained volunteers to canvass the crowds inside.

Volunteers bearing clipboards and trailing floating balloons in the campaign’s signature “liberty green” fanned out across the event space. It was a smart way to have a visible presence at the event while still focusing on organizing, Iowa Democrats said.

But as Warren takes over the lead from Biden, she’ll likely attract some of the negative attention that had previously been directed at the former vice president, Paul said.

“It’s going to be interesting to see if the other campaigns step up their contrast with her — although I’m not sure they have much of a choice anymore,” he said. “She has frontrunner status now, and with that comes the responsibility of increased scrutiny and increased contrast from the other campaigns.”

The poll also revealed some vulnerabilities for Warren: Her supporters are not completely locked in. According to the poll, just 12% of Warren’s backers say they are fully committed to caucusing for her, and 88% say they could still be persuaded to support someone else.

“Obviously one of the things they have to be concerned about is the fact that 88% ... are still willing to consider another candidate,” said Eric Woolson, a Republican operative who worked for Biden's first presidential campaign, in 1987. “So they have to make sure they don’t peak too soon. But she has the feel of somebody who has some real staying power.”

Biden and Sanders slip

Biden and Sanders — who have held first and second place, respectively, since last December — have hit new lows, though they still outshined 16 other candidates. The numbers aren’t bad, Selzer said, but the downward trend line is troubling.

Biden has fallen from 32% last December to 20% today. In that time, his favorability rating also has fallen: 82% of likely Democratic caucusgoers had a favorable view of him in December, compared with 66% today. His unfavorable numbers have nearly doubled in that time from 15% to 29%.

“I would want to pay very close attention to how the vice president broadens his inner circle to hear additional voices and take additional counsel about this campaign," Paul said. "… Specifically for the VP, he’s got to let some of the Iowa leadership team and some new folks into his inner circle.”

Though some of Biden’s gaffes and missteps here have been high-profile, Henderson said she’s not sure those stumbles have hurt him so much as the fact that other candidates are encroaching on his perceived lane as the most “electable” candidate in a general election.

“When do we start looking at ‘electability’ as who is able to create the organization and the campaign that is needed to win a general election battle?” she said, arguing that Warren’s campaign strategy and organization surpasses that of Biden’s. “(Warren’s) campaign has shown that they know how to build the organization, build the infrastructure to message and talk to people where they are at.”

Sanders, too, has stumbled, falling from a high of 25% in March to 11% today. Even among those who say they caucused for Sanders in 2016, 25% say they will do so again. He loses 32% of his 2016 supporters to Warren and 12% to Buttigieg.

Pete Buttigieg and Kamala Harris

The portion of likely Democratic caucusgoers who say South Bend, Indiana, Mayor Pete Buttigieg is their first choice for president has dropped by 6 percentage points since the June poll, from 15% to 9%. But Paul said he remains in a competitive position in part because of his fundraising ability.

“He’s clearly got resources, you saw those at (the Polk County Steak Fry),” Paul said, referencing the robust presence the Buttigieg campaign had at the Saturday event. “He’s in a strong position. He did see some erosion there. But the intensity of his support is significant. And that, plus the financial muscle that he has demonstrated gives him the opportunity to see some growth.”

Buttigieg also polled among the highest in terms of supporter enthusiasm.

Buttigieg told reporters said he’s encouraged by the polling numbers.

“You need to be in the hunt,” he said. “And each of the recent polls shows that we’re in the hunt. You need to have the resources to compete and go the distance, and we have that. And you need a good ground game, and I think today we demonstrated that we have the best ground game in the state.”

He said he was interested to see that the race remains fluid.

“It was interesting to see that only one in five voters have made up their minds for sure,” he said. “I think that’s very encouraging for us because one of the things we’ve seen is the more voters that see my campaign and our message, the more likely they are to support it. So we’ve got a lot of upside, and it just means we have to get out there and do the work. … It remains challenging. But it also means that, for a campaign like ours, we’re in a great position to compete.”

U.S. Sen. Kamala Harris of California follows Buttigieg in the poll, remaining at fifth place with 6% — the same position she was in over the summer.

Even before the Iowa Poll was released, Harris’ team acknowledged that the senator was not doing as well here as she needs to be, telling reporters they would refocus with an emphasis on Iowa.

Harris went on a five-day bus tour of Iowa over the summer and then was absent from the state for four weeks. Had she been here, Paul said, she might have seen better numbers.

“But, I give her credit for addressing it,” he said. “If she’s consistent in following up and being here, I think she certainly has got a lot of potential.”

Paul said candidates don’t need to commit to extended, three- and four-day bus tours across the state. But they should be here often from now through Caucus Day.

“We’re at the point now where the minimum these candidates need to be in the state is every other week. Minimum,” he said. “This group of candidates has been fascinated by long extended trips. I get this, but considering the news cycles that we’re in now, if I had to choose between five days in August in a row or a day-and-a-half the first week, a day-and-a-half the third week, and a day-and-a-half the final week — I’d choose the latter.”

Lower-polling candidates

“Two percent (in a poll) means different things to different candidates,” said Woolson, who managed Mike Huckabee's campaign when the former Arkansas governor came from behind to win the Republican caucuses in 2008. “To Andrew Yang and Tulsi Gabbard, 2% is not bad. It’s something to build on. When you’re running either a low-budget or new candidate campaign, it gives you something to build on. Huckabee was at less than 1% in March of ’07 and ends up winning the caucuses.”

More: A guide to all the Democrats running for president and what likely Iowa caucus participants think of them

But 2% is a more troubling number for candidates who have previously polled higher, Woolson said, pointing to former U.S. Rep. Beto O’Rourke of Texas.

“If you’re Beto O’Rourke, I think what that says is voters have looked at him and they clearly see that there’s less there than meets the eye,” Woolson said.

Several of the lower-polling candidates pointed to numbers in the poll that show the field is far from settled. Just one in five likely Democratic caucusgoers say their minds are made up, while 63% say they could be persuaded to support a different candidate.

"The poll shows that the race remains wide open,” said Alberto Lammers, spokesman for billionaire activist Tom Steyer, who registered 2% in the poll. “Iowans want real economic leadership. With extraordinary business experience and a history of fighting against corporations, Tom is the right candidate to call out Donald Trump for who he is: a criminal, fraud and failure."

Gabbard and Bennet addressed reporters at an event in Des Moines Sunday. Gabbard, who is one qualifying poll away from making the October debate stage, said that, “debate or no debate, we’re moving forward.”

Bennet, who recently went all-in with a big Iowa television ad buy, said he wished the poll had come out in a few weeks after Iowans have had a chance to see those ads. But overall, “I’d rather be at 0 than 30” at this point, he said.

Addisu Demissie, campaign manager for U.S. Sen. Cory Booker of New Jersey, posted to Twitter urging readers to “put aside the horse race” and consider the 2 percentage point rise in support and the 5 percentage point rise in his favorability rating since the Register’s last poll in June.

Booker’s team earlier in the day released a memo with a dire plea to his supporters: The campaign said it needed help raising $1.7 million during the next 10 days.

“If we don’t raise that money, we’ll have to have a serious moment of introspection,” Booker said in an interview with the Des Moines Register.

His campaign said Saturday it saw its best single-day online fundraising haul after issuing the memo, generating more than $300,000 in contributions — about 17% of its overall goal.

But Paul cautioned that Booker and other campaigns polling in the low single digits will likely have to have some difficult conversations in the coming days and weeks.

He said low poll numbers make it hard to fundraise, and a lack of cash flow makes it impossible to sustain a large campaign staff like Booker’s, which was among the first to scale up quickly.

“He’s got a big operation and that requires a healthy cash flow,” Paul said. “If they’ve got a cash flow problem, plus their numbers are just not moving, it’s hard to come out of that. A really tough conversation’s going to happen around that.”

Des Moines Register reporters Ian Richardson, Nick Coltrain and Shelby Fleig contributed to this report.

Brianne Pfannenstiel is Chief Politics Reporter for the Register. Reach her at bpfann@dmreg.com or 515-284-8244. Follow her on Twitter at @brianneDMR.

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