Minnesota Democratic Sen. Amy Klobuchar is expected to announce she's running for president on Sunday afternoon, joining a crowded and historically diverse field of candidates seeking to defeat President Trump.

She would be the fifth Democratic senator to launch a White House bid, with others still contemplating joining a primary field that has grown to 11 candidates.

The 58-year-old Klobuchar was elected to the Senate in 2006 — the first female senator from Minnesota — and has been re-elected easily twice since. Before coming to Congress, she was the Hennepin County Attorney for eight years, serving as the chief prosecutor for the state's largest county, which includes Minneapolis. In that role, she secured almost 300 murder convictions and worked to curtail gun crimes.

Her prosecutorial style was on display during last year's hearings for now-Supreme Court Justice Brett Kavanaugh , who was accused of sexual assault when he was younger. Klobuchar pressed Kavanaugh on whether he had ever been drinking so much he had blacked out and the defiant nominee threw the question back at her. Kavanaugh would later apologize, but the issue was deeply personal for Klobuchar, whose father, a well-known sports columnist in Minnesota, was an alcoholic.

In the Senate, she's championed consumer protection issues, backed stricter online privacy regulations and worked on lowering the cost of prescription drugs.

Klobuchar isn't as progressive as some of her potential Democratic competitors. She hasn't supported a Medicare for All plan, though she has said it "should be considered," and she hasn't called for other far-left ideas such as abolishing Immigration and Customs Enforcement all together. Klobuchar is seen as more of a pragmatist on Capitol Hill, with her vote rankings typically putting her somewhat in the middle of the Democratic caucus. Compared to many of her colleagues, Klobuchar hasn't sought the media spotlight that much — until recently.

Klobuchar's expected announcement is no surprise. She's been making political visits to neighboring Iowa for several year and has hinted for a long time she was seriously weighing a run.

"I will say that I have made very clear that I am looking at this," she told MSNBC on Jan. 15 . "I also had said I wanted to talk to my family, so big news today: My family is on board, including my in-laws, showing some momentum. But I will make this decision on my own course regardless of what other candidates are doing."

She also has argued that her background and geographical base could help her in a general election, as opposed to other candidates. The Midwest helped Trump win his unexpected victory in 2016, and Klobuchar has made the case that she could help Democrats be competitive in more blue collar, rural areas where they've been lacking, giving off a possible "Minnesota Nice" vibe. The title of her 2015 autobiography was The Senator Next Door: A Memoir from the Heartland.

"I think that there are a lot of good people considering this, but I do think you want voices from the Midwest. And I think you want to have people with different views running," Klobuchar told The New Yorker in Dec. 2018 .

Klobuchar is scheduled to head to Iowa again later this month, with a speaking engagement on Feb. 21 outside Des Moines.

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