DES MOINES – Hailey Dickinson can't participate in the Iowa caucuses. She's just 16 and, even if she were old enough to vote, she lives in the St. Paul suburb of Oakdale. While the high school junior can't drive either, that didn't stop her from getting up before dawn Friday to catch a ride to Iowa to spend a day off school knocking on doors for U.S. Sen. Elizabeth Warren of Massachusetts.

"Iowa sets the stage for everything," Dickinson said. "If we can get Elizabeth to win here, if she can start out strong, we can hopefully keep the momentum and finish up strong."

With the days ticking down to Monday's first-in-the-nation caucuses, carloads of volunteers from Minnesota have made trips down I-35 in ice and snow to try to persuade Iowans to side with their preferred candidates, ranging across the entire Democratic field. For some, it's a release of pent-up exuberance; for others, a chance to shape the outcome of a contest before Minnesota's primary on March 3.

The inflow includes some of the state's most visible Democrats, including Gov. Tim Walz and U.S. Rep. Ilhan Omar. Both are hitting the trail for this weekend's final push: Walz on behalf of Minnesota U.S. Sen. Amy Klobuchar, and Omar for Vermont U.S. Sen. Bernie Sanders.

There is no official tally, but the anecdotal evidence suggests that Iowa is seeing a surge of energy from Minnesota in 2020, and not just because Klobuchar is in contention.

"I can't go anywhere in Iowa without bumping into a Minnesotan," said Minnesota DFL Chair Ken Martin.

For some politically engaged Minnesotans, pre-caucus campaigning is something of a quadrennial tradition.

Surrogates and volunteers can play a key role in the field, helping candidates cover more ground and reach more voters in the lead-up to the vote. And recruiting from a border state makes sense given the proximity and regional similarities.

But the extra support has become especially crucial in recent weeks, as Klobuchar, Warren and Sanders have been stuck in Washington for the impeachment trial of President Donald Trump. Klobuchar has leaned heavily on proxies, including daughter Abigail, U.S. Rep. Angie Craig and Olympic gold medal curling coach Phill Drobnick. Walz and Lt. Gov. Peggy Flanagan also are part of her final Iowa ground game.

They will follow St. Paul Mayor Melvin Carter and Duluth Mayor Emily Larson, who courted voters Friday on behalf of Klobuchar at a brick-walled coffee shop in Ames.

"Unfortunately, I'm one of those Iowans still shopping," Donna Gilligan, a 62-year-old independent contractor from nearby Nevada, Iowa, told Larson.

Larson was ready with a pitch.

"I'm here because I am a big fan of Amy," she said. "She's great to work with and is very reliable."

Gilligan had hoped to meet the Minnesota senator, one of the few candidates she has yet to see in person during the campaign.

While she remains torn between former South Bend Mayor Pete Buttigieg and Klobuchar, she said Larson's testament was reassuring.

"Honestly, in the big picture the surrogates are critical because then you know they're not alone," she said. "They can answer the question, 'What does she represent and what does she value?' "

Forty miles south, Omar addressed a packed room of Sanders backers preparing to knock on doors in Des Moines. Many in the room had traveled to Iowa from other states to mobilize caucus­goers.

"It is really important that people understand the power that they get to have once they are counted," Omar said. "We get to remind people that they are not really only going [to caucus] for themselves, they are going on behalf of all of us."

The crowded field of Democrats has motivated some Minnesotans to increase their commitment, or even volunteer for the first time.

Katie McMahon, a singer from south Minneapolis, has traveled south almost every weekend for the past month to canvass for Buttigieg in rural parts of the state. The only Saturday she missed, she said, was due to a snowstorm.

McMahon, a native of Ireland, said Buttigieg's message of unity inspired her to get involved in her first presidential campaign.

She's found most Iowans are receptive to overtures from their neighbors to the north.

"Surprisingly, they really love the idea that we had driven so far to talk to them," she said. "Most of them were Vikings fans, so that was another thing we got to talk about."

Chris Russert, a Sanders supporter who attends Minnesota State University, Mankato, is also a newcomer to presidential campaigning. At first, the very idea of campaigning far from home was intimidating for the self-described introvert. But last weekend, the 20-year-old from Nebraska crammed into his Nissan Altima and drove three hours south to canvass, call and cheer for Sanders. One of the events featured a more high-profile Sanders surrogate: U.S. Rep. Alexandria Ocasio-Cortez.

"I can either get so frustrated with the way the system is working that I can tune out or ... turn out and make a difference," Russert said.

For some newly minted Minnesota activists, the work doesn't stop with persuading Iowans to caucus for their candidate.

Dickinson, the high school student from Oakdale, said she aims to go beyond conversion as she tries to arm potential supporters with arguments and information they can use on undecided neighbors during the caucuses.

By the time she wrapped up at a campaign office in Ankeny on Friday evening, she'd knocked on an estimated 100 doors over the course of two daylong trips.

But Dickinson wasn't done. She said she planned to return at least one additional day this weekend, and possibly Monday if her parents let her skip school.

"[We're] pushing through to the finish," she said. "I'm tired, everyone is tired, but after Iowa is over we're going to take a little breath and get ready for the Minnesota primary."