The 83 pledged delegates are awarded proportionally.
It is now mathematically impossible for Sanders to clinch the Democratic nomination using only pledged delegates, based on ABC News delegate estimates.
This means the only way Sanders can reach the magic number of 2,383 delegates is with the support of superdelegates.
Still, Sanders told reporters this evening, "I understand that Secretary Clinton thinks that this campaign is over. I’ve got some bad news for her. I know all the pundits thought we were supposed to lose but that apparently is not what all the people of Indiana concluded.”
Sanders also scoffed at the idea that staying in the race could hurt Democrats' chances against GOP front-runner Donald Trump. "Not at all. Not at all,” he said. He pointed to polls that showed voters saying the primary invigorated the party. "I have no doubt, zero doubt that what we have done in this campaign, what we are doing now and what we will do in the next 6 weeks is good for the democratic party and it will result in a higher voter turnout," he added.
It will likely remain mathematically possible for Sanders to win the Democratic nomination until at least June 7 because the large number of superdelegates, who overwhelmingly back Clinton now, but are free to change their minds.
Clinton currently needs to win 70 percent of remaining delegates in order to clinch the Democratic nomination using only pledged delegates.
Neither of the Democratic candidates are in Indiana tonight, as Clinton was campaigning in Ohio and Sanders was campaigning in Kentucky. Clinton does not have any events planned tonight but Sanders did speak publicly tonight.