Amy Klobuchar is ending her bid for the 2020 Democratic nomination, and plans on endorsing Joe Biden at a rally in Dallas on Monday evening — the night before Super Tuesday.

Ms Klobuchar, a senator from Minnesota, was not expected to perform when 14 states take to the polls on Tuesday representing the largest delegate haul of the season, and her decision to drop out marks the latest signal that moderate Democrats are attempting to coalesce around Mr Biden and give him a fighting chance against the race's front-runner, Bernie Sanders.

Just a day before Ms Klobuchar's decision was made public, fellow midwesterner Pete Buttigieg announced he was withdrawing as well.

From the moment Ms Klobuchar announced her long shot bid for the Democratic nomination last February, Ms Klobuchar has failed to garner much enthusiasm in polls or from the press, even as she cast her self as the pragmatic choice for voters to take on Donald Trump in November.

Her presidential run was given a momentary boost following the New Hampshire primary, where she came in third-place, but has otherwise performed poorly in the other three states that have voted so-far.

Democratic candidates compete on the campaign trail: In pictures Show all 18 1 /18 Democratic candidates compete on the campaign trail: In pictures Democratic candidates compete on the campaign trail: In pictures Jessica Canicosa, a precinct captain for Bernie Sanders, waits to greet caucus voters at Liberty High School in Henderson, Nevada REUTERS Democratic candidates compete on the campaign trail: In pictures Hotel workers at the Bellagio in Las Vegas get to grips with voting papers during the Nevada caucuses AFP via Getty Images Democratic candidates compete on the campaign trail: In pictures A caricature of Bernie Sanders is projected on to a tree during a rally in Las Vegas EPA Democratic candidates compete on the campaign trail: In pictures A woman waits to have a photo taken with Elizabeth Warren during a town hall meeting in Las Vegas REUTERS Democratic candidates compete on the campaign trail: In pictures The threat of coronavirus and other germ-borne illnesses was on some voters' minds at the Democratic caucuses in Henderson, Nevada Getty Images Democratic candidates compete on the campaign trail: In pictures Former vice-president Joe Biden takes a selfie with a voter in Las Vegas ahead of the Nevada caucuses REUTERS Democratic candidates compete on the campaign trail: In pictures Amy Klobuchar changes her shoes backstage after giving a speech in Exeter, New Hampshire AFP/Getty Democratic candidates compete on the campaign trail: In pictures A warmly-wrapped-up dog attends an Elizabeth Warren event at Amherst Elementary School in Nashua, New Hampshire AFP/Getty Democratic candidates compete on the campaign trail: In pictures Bernie Sanders, who romped to victory in New Hampshire against Hillary Clinton in 2016, talks to the media in Manchester Getty Democratic candidates compete on the campaign trail: In pictures Joe Biden was hoping to improve on his poor showing in Iowa in the New Hampshire primary Reuters Democratic candidates compete on the campaign trail: In pictures Elizabeth Warren, renowned for giving time to supporters for selfies, works the crowd at the University of New Hampshire in Durham Getty Democratic candidates compete on the campaign trail: In pictures Joe Biden takes a selfie with a supporter and his child outside a campaign event in Somersworth, New Hampshire on 5 February Reuters Democratic candidates compete on the campaign trail: In pictures Elizabeth Warren and Bernie Sanders quarrel after a confrontation in a TV debate in which Sanders claimed that Warren was not telling the truth about a conversation in which she claimed he had said a woman could not win the presidency on 14 January AP Democratic candidates compete on the campaign trail: In pictures Supporter Pat Provencher listens to Pete Buttigieg in Laconia, New Hampshire on 4 February Getty Democratic candidates compete on the campaign trail: In pictures Pete Buttigieg speaks at a campaign event in Concord, New Hampshire while awaiting the results of the Iowa caucus Reuters Democratic candidates compete on the campaign trail: In pictures Elizabeth Warren is presented with a balloon effigy of herself at a campaign event in Nashua, New Hampshire on 5 February Reuters Democratic candidates compete on the campaign trail: In pictures A Trump supporter rides past a rally for Amy Klobuchar in Des Moines, Iowa on 14 January AP Democratic candidates compete on the campaign trail: In pictures A man holds up a sign criticising billionaires in the presidential race in front of Michael Bloomberg in Compton, Califronia. The former New York mayor skipped the first caucus in Iowa and instead campaigned in California on 3 February Reuters

Her home state of Minnesota is among those that will vote on Tuesday, and it was that contest that she appeared most likely to do well in, with Mr Sanders, Mr Biden and Michael Bloomberg sucking up the attention across most of the rest of the country.

Her endorsement of Mr Biden comes following considerable consternation among moderate Democrats that Mr Sanders is amassing a formidable delegate lead that could become insurmountable after Super Tuesday.

Still, even with that focusing of establishment support behind Mr Biden — the former vice president's campaign announced a series of endorsements on Monday before Ms Klobuchar's decision was known — it is unclear that the Vermont senator's momentum can overcome, especially given his strong support in western states and delegate rich California, which votes on Tuesday.

And, with 46 states left to vote, early forecasts have indicated a contested convention may be the most likely outcome of the race.