Sen. Amy Klobuchar is set to reveal whether she will run for president at a rally Sunday in Minneapolis.

The Democratic senator from Minnesota will make her announcement at a 1 p.m. event at Boom Island Park, across the Mississippi River from downtown Minneapolis.

A spokeswoman said Tuesday that Klobuchar would not say until the event itself whether she will seek the Democratic presidential nomination in 2020. A news release says only that Klobuchar will make a “major announcement” to a crowd of Minnesotans and supporters.

The field of potential challengers to President Donald Trump is large and growing, and a number of Klobuchar’s allies and advisers believe she is joining the race.

“Yes, I would like to see her run,” Gov. Tim Walz said in a recent interview. “I think she brings a leadership style that is reflective of the Midwest, reflective of the values and the best of Minnesota. She is popular and is a very hard worker.”

Klobuchar has stated in numerous recent interviews and TV appearances that she is considering a presidential bid. She went so far as to say that her family was on board with a national campaign.

If Sen. Amy Klobuchar joins the 2020 race, her proximity to Iowa will be an advantage.

Klobuchar has also described a political rationale for her candidacy: She’s a popular senator from the Midwest, a region where Trump flipped several usually Democratic-leaning states in 2016.

“I think you need people who can relate to the Midwest,” Klobuchar told the Star Tribune in early January. First elected to the Senate in 2006, Klobuchar racked up big winning margins in all three of her statewide runs. Last year, she carried 43 Minnesota counties that Trump had carried just two years earlier, on her way to winning a third term.

The competition among Democratic contenders will be fierce. Already, four of Klobuchar’s Senate colleagues are running: Elizabeth Warren of Massachusetts, Kirsten Gillibrand of New York, Kamala Harris of California and Cory Booker of New Jersey. Former Vice President Joe Biden, Vermont Sen. Bernie Sanders, former Texas congressman Beto O’Rourke and former New York City Mayor Michael Bloomberg might run, and other current and past elected officials.

“How do you break through in a field this large? She’s got work to do on the tactical level to break through as much as she can every day,” said Jeff Blodgett, a Minnesota Democratic strategist and longtime adviser to Klobuchar.

The obvious first step for a candidate from Minnesota is Iowa, with its first-in-the-nation presidential caucus on February 3, 2020. Politico reported Tuesday that Klobuchar will headline a Feb. 21 Democratic Party dinner and fundraiser in Ankeny.

“I think she will have an advantage there because of proximity,” said Joe Trippi, a D.C.-based Democratic strategist who worked on multiple presidential campaigns. “This won’t be the first barn or cornfield that she’s stood in.”

A lesser-known candidate who manages to pull off a win in Iowa, or at least a strong finish, would immediately vault into the top tier of candidates, Trippi said. He managed former Vermont Gov. Howard Dean’s presidential campaign in 2004, and also worked on the campaign of former Vice President Walter Mondale back in 1984.

The permit application for Klobuchar’s Sunday event bills it as a “Bold North Winter Celebration.” Klobuchar plans to make her remarks outside. The forecast on Sunday calls for a high temperature of 16 degrees.