2020 Democratic presidential-nomination campaigns are ramping up organizing efforts by expanding staff and engaging with local communities in the crucial summer months with the Iowa caucuses on the political horizon.

Candidates and campaign organizers have swarmed into Iowa with increasing frequency as they attempt to establish support and stand out from the crowded field of 23 Democratic candidates before the first debates on June 26-27.

With more than 50 paid staffers across Iowa, Sen. Elizabeth Warren’s campaign has established an early presence in the state. The campaign has hosted a plethora of small organizing events in eastern Iowa since Warren announced her candidacy in early 2019.

Warren Iowa Communications Director Jason Noble said he views grassroot-organizing efforts by staff as essential to building support for the Iowa caucuses.

“Clearly, we have a really robust staff all across the state, and that includes in college communities and on campuses,” Noble said.

Sen. Kamala Harris’ campaign announced on June 6 it will expand the Iowa staff exponentially from five to 65 staffers by July 1. The staff growth will place the Harris campaign as the largest Iowa employer among the Democratic candidates.

“Our staff on the ground has been going to local events, going to [meet people] one-on-one, and working to get people involved and excited about the campaign and about Kamala Harris,” said Mariah Gould, Harris’ regional organizing director for the Iowa City area. “We had a really good response so far, and it seems like a lot of people are really interested in Kamala Harris.”

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The campaign works on the ground to engage Iowans by connecting them with the campaign and providing information on getting involved, Gould said.

“I think we want to make sure we have a combination of both grassroot efforts and volunteer efforts, and I think both of those things play into each other,” she said.

The campaign of former Texas Rep. Beto O’Rourke also prioritizes volunteer involvement to expand its support in Iowa. O’Rourke Iowa Communication Director Geoff Burgan said the campaign held 18 canvassing events in nine cities last weekend as part of the campaign’s statewide weekend of action.

The O’Rourke campaign in Iowa employs 44 staff members, 37 of whom are responsible for organizing, Burgan said. The staffers focus on spreading information about O’Rourke through the internet, town halls and community meetings, he said.

Despite many students’ absence from college campuses this summer, Burgan said, the months will be an important time for campaign organizing. O’Rourke previously targeted student voters in Iowa by visiting the three regent universities.

“Summer is when the hard work really happens,” he said. “You get to see when campaigns are more serious about the organizing part of the caucuses. We certainly want to be part of that conversation.”

Cynthia Sebian-Lander, the Iowa state director for Democrat Julián Castro, said the campaign also takes advantage of the summer to train and distribute campaign staff.

She said her campaign sends organizers to meet with communities by participating in local Democratic committee meetings and placing information tables at community events, among other things. She said has seen momentum build, she said, and has witnessed growing excitement for Castro in various communities.

Despite employing significantly fewer staff members than such campaigns as Warren’s and Harris’, Sebian-Lander said the Castro campaign is focused on talking to specific voters and gathering support instead of paying attention to the actions of other campaigns in Iowa.

“We know who we need to go talk to, and we are excited for the opportunity to talk with folks who are too often left out of the process and don’t always feel like the caucus is a stage for them to participate,” she said.