Transcript for Sen. Bernie Sanders returns to campaign trail after heart attack
To the race for 2020. A massive rally marking a return to the campaign trail, Democrat Bernie Sanders after his heart attack and a big endorsement. ABC's Rachel Scott was there with what the supporters are saying about the Sanders comeback. Rachel, good morning. Reporter: Good morning. Yes, it's been three weeks since that health scare but senator Bernie Sanders is bouncing back, bringing in new endorsements and bringing out the largest crowd we've seen in the democratic primary so far. I am back. Reporter: Senator Bernie Sanders flexing his campaign muscle, pushing past a recent heart attack to reassure his supporters he's up for the challenge. I am more than ready to assume the office of president of the United States. Reporter: More than 25,000 packing a park in queens, new York making Sanders' rally the largest for any Democrat in the 2020 campaign. His return to the campaign trial stamped with a coveted endorsement. Holy cow. Reporter: Congresswoman Alexandria ocasio-cortez -- What's up, New York City! Reporter: -- Praising the crowded field of Democrats but throwing her support behind just one. We have one of the best democratic presidential primary fields in a generation, and much of that is thanks to the work that Bernie Sanders has done in his entire life. Reporter: His supporters hope that endorsement gives Sanders who has slipped in the polls a boost. I think seeing women of color, the van guard of the new left endorsing Bernie, it means everything to me as a young person. Reporter: The other candidates out and about in key early voting states. Hello, Virginia. Reporter: As an unexpected feud plays out in the race. Former democratic presidential nominee Hillary Clinton without evidence suggesting Russian influence in the primary. I think they've got their eye on somebody who's currently in the democratic primary and they're grooming her to be the third-party candidate. She's the favorite of the Russians. Reporter: Congresswoman Tulsi gabbard believed she was the target of that attack, firing back calling Clinton the queen of warmongers and even challenging her to join the race. Clinton's team has not responded to our request for comment but president trump is weighing in on this disagreements, lashing out at Clinton, guys. It's good to have you inside. You've been all over the country traveling. It's a lot warmer in the studio. You've been doing great work.
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