Here's what Bernie Sanders would need to beat Joe Biden to the Democratic nomination, against almost impossible odds

• After a series of losses to former Vice President Joe Biden in Tuesday night's Democratic primaries, Sen. Bernie Sanders' presidential candidacy looks all but over.
• There is still a route for Sanders to clinch the Democratic nomination, but it would require overcoming huge odds in states, including Florida and Georgia, that have shown little enthusiasm for his candidacy.
• And if Biden's leads in current polls translate into sweeping wins in next Tuesday's primaries, Sanders will face increasing pressure to concede.
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Four years ago, Sen. Bernie Sanders' shock win against Secretary Hillary Clinton in Michigan gave his outsider campaign a much-needed boost. Last night his crushing defeat in the state to centrist rival, former Vice President Joe Biden, left it in tatters.

With 1,991 delegates needed to clinch the Democratic presidential nomination, Sanders trails his rival with 670 delegates to Biden's 820 after Tuesday's results.

Though Michigan was the biggest prize in terms of delegates on Tuesday night, Biden also won primaries in Missouri, Mississippi and Idaho. You can see Business Insider's live updates of the various results here.

In an apparent acknowledgement of the scale of the defeat, Sanders did not deliver a speech to supporters to rouse them after Tuesday, remaining silent after returning to his home state of Vermont.

That being said, Sanders could still claim victory on paper. But it would require surmounting almost impossible odds, according to polling data in states where the next major primaries will be held next Tuesday.

• In Arizona, where there are 67 delegates up for grabs, Biden currently holds a 28-point lead over Sanders, according to an OH Predictive Insights poll released Monday.
• The largest delegate haul next Tuesday is in Florida, where there are 219 up for grabs. Here Biden currently has a 36-point lead, according to a Florida Atlantic University poll conducted between March 5 and March 7.
• Sanders' strong showing in the Texas and California primaries last week was largely owing to support from Latino Democrats. But in Florida the picture is different: Biden polls ahead of Sanders among Latino voters in the state, with 48% of the vote to 37%, according to a survey conducted for Telemundo Station Group by Mason-Dixon between March 5 and March 7.
• As recently as February 20, Sanders held a narrow 5-point lead in Illinois, where there are 155 delegates. But that lead has slipped away, and Biden now has a 29-point lead, according to a March 8 poll by Ogden and Fry.
• The most recent poll for Ohio, where there are 136 delegates, was between January 8 and January 20, where Baldwin Wallace found that Biden had an 11-point lead.
• In Georgia, which will hold its primary on March 24, Biden has an 18-point lead over Sanders, according to a February 18 poll by Landmark Communications on February 18. Support from African-American voters has been key for Biden so far, and black voters in the state are again expected to back him over Sanders.
• In another bad omen for Sanders, back in 2016 his rival, Hillary Clinton, beat him in each of the four states where voters will go to the polls on Tuesday.

In order to overcome Biden's lead, Sanders now needs to win the vote of 55% of the delegates still up for grabs, according to Politico.

But doing that would require a stunning reversal of Biden's polling lead, and if that fails to happen, Sanders will likely be forced to drop out next week or sooner.