Does Sanders still have a path to Democratic nomination? What it would take for him to win

Bernie Sanders’ path to becoming the Democratic presidential nominee considerably narrowed this week, after Joe Biden won a majority of Tuesday’s primaries, opening a commanding delegate lead over the Vermont senator.

But Sanders, on Wednesday, said he intends to remain in the presidential race and participate in the one-on-one debate with Biden in Phoenix this Sunday despite his lackluster performance in the latest series of nominating contests.

Biden dealt a crushing blow to Sanders when he won four of the six primary states on Tuesday, including the biggest delegate prize of the night, Michigan. According to the Associated Press’ delegate tracker, Biden leads with 864 delegates, while Sanders has 710 -- a nearly insurmountable gap to overcome.

To wrest the nomination from Biden, Sanders needs to win 57 percent of the remaining delegates, a difficult and historically unlikely feat. More than half of delegates are still available in the upcoming primaries.

BIDEN DEFEATS SANDERS IN KEY STATES, SECURES NEARLY INSURMOUNTABLE DELEGATE LEAD

Candidates need to secure 1,991 delegates of the 3,979 pledged delegates to clinch the nomination. More than half of the pledged delegates have not yet been allotted, meaning that Biden cannot mathematically win the nomination until at least April 28.

Biden is favored in upcoming delegate-rich states, including Florida and Ohio. And if he continues to perform as well as he has, he could win the nomination by the end of April or early May, according to New York Times calculations. According to an aggregate of national polls by RealClearPolitics, Biden leads by close to 17 percentage points.

SANDERS VOWS TO STAY IN 2020 RACE AS BIDEN CLOSES IN ON DEMOCRATIC NOMINATION

But it’s possible that Biden could lose his delegate majority. The Times estimated that he could do about 12 percentage points worse than he has and still win a majority -- but if he fares any worse, he could fall short and risk a brokered convention. However, Sanders has said that if Biden has a plurality of delegates when he enters the Democratic convention in Milwaukee this summer, he should be the party’s nominee.

"If Biden walks into the convention or at the end of the process has more votes than me, he's the winner," Sanders told MSNBC’s Rachel Maddow at the beginning of March.

SANDERS' 2020 EXPECTATIONS DERAILED BY BIDEN'S COMEBACK

According to the Times, if Sanders performed about 17 percentage points better, he could receive a plurality of delegates. That essentially means he’d have to win the vote share in all but a few of the rest of the states to secure a plurality. But to capture a majority of delegates, Sanders would need to perform roughly 21 percentage points better.

Ohio, Illinois, Florida and Arizona are the next states to hold nominating contests on March 17.