Bernie Sanders came in a distant second place, with Tom Steyer in third despite devoting millions of dollars to the state contest (He has now announced that he is dropping out of the race)

As to the effect on the election, I think that this is generally bad news for Sanders, who underperformed IMHO, and Michael Bloomberg, who, while not on the ballot, has been selling himself as an alternative to a flagging Biden campaign.

Super-Tuesday is in 3 days, and I have no predictions beyond that  some of the also-rans are likely dropping out after that.

Joseph R. Biden Jr. scored a decisive victory in the South Carolina primary on Saturday, reviving his listing campaign and establishing himself as the leading contender to slow Senator Bernie Sanders as the turbulent Democratic race turns to a slew of coast-to-coast contests on Tuesday.

Propelled by an outpouring of support from South Carolina’s African-American voters, Mr. Biden easily overcame a late effort by Mr. Sanders to stage an upset. The victory in a state long seen as his firewall will vault Mr. Biden into Super Tuesday, where polls open in just over 48 hours, as the clear alternative to Mr. Sanders for establishment-aligned Democrats.

Mr. Biden, the former vice president, captured just under 50 percent of the vote, well ahead of Mr. Sanders, who had 20 percent. Tom Steyer, the California billionaire, was a distant third, followed by Pete Buttigieg and Senator Elizabeth Warren of Massachusetts. The victory enabled Mr. Biden to significantly narrow Mr. Sanders’s pledged delegate lead, but he did not appear poised to overtake him.