Bernie Sanders has defied powerful critics and risen from long-shot 2016 candidate to 2020 Democratic frontrunner

Associated Press

Democratic presidential candidate Sen. Bernie Sanders, I-Vt., stands on stage with his wife Jane Sanders, left, after speaking at a campaign stop at the Whittemore Center Arena at the University of New Hampshire, Monday, Feb. 10, 2020, in Durham, N.H. (AP Photo/Andrew Harnik)

• Sen. Bernie Sanders is the 2020 frontrunner after strong performances in both Iowa and New Hampshire.
• Sanders won in New Hampshire and was in a virtual tie in Iowa with former South Bend Mayor Pete Buttigieg, though the results of the Iowa caucus are still being disputed.
• Sanders is at the top of national polls, and far ahead of the 2020 field in terms of fundraising. He raised a whopping $25 million in January alone.
• The Vermont senator is dominating the 2020 field in fundraising, but there's a long way to go and many delegates still up for grabs.
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Sen. Bernie Sanders became the 2020 frontrunner on Tuesday night with an important win in the New Hampshire primary. In just four years, he's gone from being a longshot candidate to leading a broad field of Democratic candidates for the party's presidential nomination, overcoming numerous naysayers along the way.

Meanwhile, Sanders has pulled the Democratic party increasingly to the left and defined the terms of the conversation in the 2020 race.

After Sanders hopped in the race last February, he led the pack among declared candidates for a time until former Vice President Joe Biden launched his bid in April. Sanders' campaign began to flatline over the summer, and questions were raised about whether he would continue to run after a heart attack in October.

But the Vermont senator rebounded rapidly, surging in the polls, dominating the field in fundraising, and nabbing key progressive endorsements as he headed into the new year.

Though the results of the Iowa caucuses are still being debated after the Iowa Democratic Party bungled the contest, Sanders appeared to be in a virtual tie for first with former South Bend Mayor Pete Buttigieg. Sanders also won the popular vote in Iowa.

Since 1972, no candidate has gone on to win a major party nomination without coming in the top two in either Iowa or New Hampshire. As of Tuesday, Sanders officially fell into that category.

While Buttigieg had strong showings in both races, also coming in the top two, he is far behind in recent national polls and has polled poorly with black voters. In short, there are signs the former South Bend mayor could struggle in upcoming primary contests and lacks Sanders' long experience in national politics.

Meanwhile, Sanders is at the top of national polls, and far ahead of the 2020 field in terms of fundraising. He raised a whopping $25 million in January alone.

Much could change in the coming months, particularly after Super Tuesday in early March when there are 16 contests in a single day. A lot of delegates, or the people who will ultimately be sent to the Democratic convention in July to vote for the nominee, are still up for grabs.

Early frontrunners do not always sustain their lead and Sanders has stiff competition. He's also self-declared democratic socialist, a label that could become a liability for Sanders in a country where approximately one-in-five people continue to view socialism as a threat to the US.

Sanders has many critics in the establishment wing of the Democratic party, which has repeatedly labeled him as unelectable and too radical.

James Carville, a veteran Democratic strategist, recently suggested to MSNBC that the party would essentially become a "cult" if Sanders wins the nomination.

"There's a certain part of the Democratic Party that wants us to be a cult," Carville said in a viral rant to MSNBC, though he later told Vox he'd vote for Sanders if the Vermont senator comes out on top. Meanwhile, former Secretary of State Hillary Clinton, who beat Sanders for the nomination in 2016, has excoriated her ex-opponent multiple times in recent months.

"He was in Congress for years. He had one senator support him. Nobody likes him, nobody wants to work with him, he got nothing done. He was a career politician. It's all just baloney and I feel so bad that people got sucked into it," Clinton said of Sanders in a new documentary that premiered in January.

In spite of his critics in the party, Sanders is off to a flying start in the 2020 Democratic primary season, and after roughly a year in the race he can be dubbed the frontrunner on multiple levels.

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