Introduction
The 2020 democratic presidential primary was the contest to nominate a candidate for the U.S. Presidential election in 2020. Depending on the state, the 'primary' is in fact a blend of primary races and caucuses. Fifty states, the District of Columbia, and five U.S. territories participated in this event, which began in January 2020 and concluded at the Democratic National Convention in Kansas City, Missouri in July that same year.

Primary Race Overview
Nine candidates joined the race for President on the Democratic side. Former Governor Martin O'Malley (D-MD) joined the race on April 12, 2019, followed by Senator Cory Booker (D-NY) and former Governor Terry McAuliffe (D-VA) in May 2019 (May 5, and May 15, respectively). Despite the early success in fundraising and a broad appeal across the east coast, Senator Booker had trouble crystalizing his campaign message. After a number of early slips within his campaign staff, Booker hired a team of professionals, including Anita Dunn and Joel Johnson. By late summer, the campaign was back on message, appealing particularly younger, left-leaning college students and millennials. O'Malley, having run unsuccessfully in 2016 against Sanders and Hillary Clinton, positioned himself as center-left advocate for promoting equal rights, particularly in the workplace (e.g., equal pay), but also as someone who was hesitant to raise taxes unless absolutely necessary. In early June, Governor Deval Patrick (D-MA) announced his candidacy, positioning himself as an outsider with governing experience. Terry McAuliffe, who had both executive experience as governor of Virginia, and a business background, appeared to be the candidate for Hillary Clinton's voter base from 2016. McAuliffe raised a substantive amount of money early on, and led many polls throughout the summer, suggesting he might be the front runner going into Iowa. His focus on both health care and fiscal responsibility hit a salient note with voters, as the recession in late 2018 had voters seeking someone placing economic stability at the top of their resume. Many were surprised that no other candidate declared their candidacy until late July of 2019. Amid a great deal of speculation and rumor, former Vice President Joe Biden (D-DE) decided to remain out of the conversation through this summer, as did Senator Elizabeth Warren (D-MA). Warren eventually opted not to run, while Biden decided not to run later the fall. Before this occurred, on July 27th, Governor Steve Bullock (D-MT) announced his candidacy for the democratic nomination. Bullock campaigned as a salve to the bitter rigidity of both Trump (R-NY) populism on the far right, and increasingly populist leaning far left wings of each other. In August, Amy Klobuchar (D-MN) and Russ Feingold (D-WI) entered the race. On September 21, former Vice-Presidential candidate Tim Kaine (D-VA) joined the list of candidates, after he perceived a "lack of enthusiasm" in the candidates, which many believe he feared would result in another 2016 outcome. The candidate list was completed in early October, when Dwayne "The Rock" Johnson announced his candidacy for the democratic nomination. This surprised many, who anticipated Johnson to challenge the sitting, although staggeringly unpopular sitting President, Donald Trump in the Republican primaries. Johnson largely cast himself as an independent, however, and felt he would have a better chance at challenging the Republican President in the general election. The first debate would be held in Philadelphia, PA later that same week. All nine candidates polled at least 1%, meaning they were all invited to participate.
The First Round of Debates[]
A total of ten debates were held from October 2019 through April 2020. An eleventh and twellth debate were scheduled, but cancelled due to Bullock's strong lead going into May. Bullock would become the presumptive nominee the first week of May, 2020. The first debate was held in Des Moines, Iowa in October, 2019. It was sponsored by CBS News and moderated by John Dickerson of Face the Nation.
In the first debate, Amy Klobuchar stood apart from her counterparts as someone unwilling to be afraid of Trump's agenda and take it on. Booker, who had been critical of the administration the previous summer, changed his tone to one of optimism, which surprised many viewers. Tim Kaine's most notable moment was when water came out of his nose; a moment that he laughed off, and most of the audience forgot (but the Internet did not) as Kaine spoke passionately about his own non-political work prior to the Senate and his experience with the Clinton campaign. O'Malley was the final winner of the night, championing a return to progressive causes that had been espoused during the Obama years. O'Malley had risen in the polls, somewhat to the surprise of the mainstream media and pollsters in the recent weeks.