By Eliza Collins 

Bernie Sanders, the progressive whose two campaigns for president pulled the Democratic Party to the left, is ending his White House bid after a series of poor performances in primaries made his path to the nomination extremely difficult.

Mr. Sanders, 78 years old, had been seen as the front-runner for the Democratic nomination in February, but a rapid consolidation of the party's establishment around former Vice President Joe Biden in early March reversed his fortunes.

The Vermont senator had long said that he would need to expand the electorate to win the nomination. Though some contests showed an increase in turnout, it was generally in Mr. Biden's favor. In many states, Mr. Sanders's strong hold on the youngest and most-liberal voters was more than offset by Mr. Biden's strength among less-liberal and older voters.

Mr. Sanders lagged Mr. Biden in polls in Wisconsin, which held its primary Tuesday and will release results April 13. Many other states delayed their primaries amid the coronavirus pandemic, meaning a long wait with no in-person campaign events before Mr. Sanders could try to stage a comeback.

He suffered several disappointing weeks in March. A 17-point loss in Michigan that month cemented his dire position. The Vermont senator had long said that in a general election, he would be able to carry Midwestern states like Michigan that narrowly voted for President Trump in 2016. Mr. Sanders had won the state in a surprise victory against Hillary Clinton in the Democratic primary that year.

It was a stark fall from the end of February, when Mr. Sanders appeared likely to cruise to the nomination. He had won Nevada by 27 points, narrowly captured New Hampshire and effectively tied for the lead in Iowa.

But the party's moderate wing began to consolidate around Mr. Biden after he won South Carolina by 28 points with the help of black voters, a key bloc of Democratic primary voters. Four former candidates backed Mr. Biden over the course of a week. Massachusetts Sen. Elizabeth Warren, the candidate closest to Mr. Sanders ideologically, also exited the race but didn't endorse anyone.

While versions of Mr. Sanders's liberal policies were broadly popular with the Democratic electorate -- a Wall Street Journal/NBC News poll from March found 67% of Democratic primary voters supported a Medicare for All system -- Mr. Sanders faced voters who prioritized getting Mr. Trump out of office and voted on what they viewed as electability rather than policy. Many of them worried that a self-described democratic socialist would be easier for the president to beat in a general election.

The senator's campaign was further hampered when he was no longer able to hold his signature large rallies or other public events because of the coronavirus pandemic. The Vermont senator livestreamed events instead.

The Sanders campaign deactivated its digital ads on Facebook as of March 18 and hadn't booked television ads since the week before. An aide said the campaign was trying to conserve resources. With his path to the nomination near nonexistent, Mr. Sanders also stopped soliciting donations for his campaign that same week, instead using the operation to fundraise for and organize around the crisis.

Mr. Sanders campaigned on the promise of a revolution that would change major sectors of the U.S. economy, with proposals to eliminate student and medical debt, make public colleges and universities free, and overhaul the economy to combat climate change. He proposed paying for his ambitious proposals by increasing taxes on corporations, the wealthy and the middle class.

His 2016 presidential candidacy popularized many of his ideas in the Democratic Party, and his 2020 bid forced every rival candidate to take a position on his signature issue, Medicare for All. Mr. Sanders -- along with Ms. Warren -- also denounced money in politics, proving that you don't need big donors to fuel their campaigns.

Mr. Sanders's candidacy stumbled after he had a heart attack in October 2019. He spent a few days in the hospital before taking some time off from the trail. He resumed campaigning in mid-October.

Mr. Sanders used his heart attack to highlight the push for Medicare for All, arguing that he was lucky to have health-care coverage for an emergency procedure when many Americans don't. He said that a government-run coverage system would make sure everyone was able to receive care.

At the same time, he brought in high-profile endorsements, including that of Rep. Alexandria Ocasio-Cortez, the popular New York lawmaker who became a draw at his campaign events.

Mr. Sanders also appeared to benefit from a drop in Ms. Warren's polling that came as she received criticism of her position on Medicare for All, which included a transition period and an expectation that the plan wouldn't be passed until her third year in office. Mr. Sanders said a bill would be put out in his first week in office.

Despite being the oldest candidate in the 2020 Democratic field, the Vermont senator had a fervent base of young supporters. But he struggled with older voters, and he was unable to rival Mr. Biden's support among black Democrats, a major constituency in states that voted in March and are yet to vote.

His political career began in 1981 when he became mayor of Burlington, Vt., winning by just 10 votes. He went on to lead the city for four terms, at times adopting a pragmatic approach to governing by working with Republicans and the business community.

He was elected to the House of Representatives in 1990 and to the Senate in 2006. Mr. Sanders has always identified as an independent but caucused with Democrats during his tenure in Washington.

Mr. Sanders became a prominent national figure during his run for the Democratic nomination against former Secretary of State Hillary Clinton in the 2016 presidential election. Mr. Sanders started in that race as a long shot, but rose to be considered a real threat to Mrs. Clinton.

She ultimately secured the nomination, but his 2016 run gave him a national profile that helped him launch his 2020 campaign as a front-runner. And many voters cited his consistency in pushing for liberal priorities, including a single-payer health system, as a reason to back his second White House bid.

Aaron Zitner, Alexa Corse and Chad Day contributed to this article.

Write to Eliza Collins at eliza.collins@wsj.com.

(END) Dow Jones Newswires

April 08, 2020 11:41 ET (15:41 GMT)

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