Amy Klobuchar has ended her US presidential bid, an aide told HuffPost.

Klobuchar is set to endorse former Vice President Joe Biden at an event in Dallas on Monday night, The Associated Press reports.

Her decision comes after a poor showing in the South Carolina primary. She picked up just 3% of the vote, flailing in comparison to her fellow moderate Biden, who walked away with 48%.

Though the Minnesota senator’s campaign picked up steam in the leadup to the first primaries and caucuses, Klobuchar’s late-stage momentum wasn’t enough to eclipse her most formidable opponents in the crowded Democratic field. 

She joins former South Bend, Indiana, Mayor Pete Buttigieg and billionaire hedge fund manager Tom Steyer in dropping out just ahead of Super Tuesday. More than 1,500 delegates will be up for grabs as Democrats across 14 states and one overseas territory head to the polls. 

Klobuchar ran as a moderate, betting that focusing on issues that could attract bipartisan support ― combating drug and alcohol addiction, preserving voting rights, antitrust enforcement ― would earn her votes. She touched on those ideas in June when she became the first 2020 contender to lay out a comprehensive plan for her first 100 days in office.

Her more moderate proposals on climate change and health care stood in contrast to the bold, progressive ones from senators Elizabeth Warren and Bernie Sanders.

Klobuchar, one of six female candidates to seek the 2020 Democratic nomination, made some headlines for calling out sexism in politics. Days ahead of the November 20 Democratic debate, she argued that Buttigieg would not have qualified for the debate if he were a woman, given his lack of experience in Washington.

Klobuchar picked up a key endorsement from The New York Times editorial board on January 19, when the publication broke from the tradition of endorsing just one candidate to show support for her and Warren. 

Throughout their campaigns, both candidates have found themselves defending their electability ― a concern their male counterparts have rarely been saddled with. Klobuchar often pointed to herself as the best evidence that such talk was unwarranted.

“When you look at what I have done, I have won every race, every place, every time,” she said during the January debate.

But despite being immensely popular in Minnesota, Klobuchar’s efforts to pitch herself as “the senator next door”, as she titled her 2015 book, didn’t always stick the landing. Cracks in her friendly Midwestern persona emerged in the early days of her campaign when multiple former staffers told HuffPost that Klobuchar had a long history of mistreating her staff.