AUDIE CORNISH, HOST:
After Hillary Clinton secured the Democratic nomination for president here at the Wells Fargo Center in Philadelphia, hundreds of Bernie Sanders' supporters walked out of the arena. From the moment this convention opened, diehard Sanders supporters have made themselves heard with boos and chants during speeches. NPR's Sam Sanders has been talking with some of his backers to see what they're thinking.
SAM SANDERS, BYLINE: The first boos yesterday came during Dr. Cynthia Hale's opening prayer - yes, the prayer.
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CYNTHIA HALE: We have an opportunity, oh God, to give undeniable evidence of our commitment to justice and equality by nominating Hillary Rodham Clinton as our candidate...
(CHEERING)
SANDERS: For the first few hours, every time the name Hillary Clinton was uttered there were boos, and then cheers came to drown them out.
(SOUNDBITE OF ARCHIVED RECORDING)
HALE: Hallelujah.
(CHEERING)
SANDERS: It's really hard to describe what it was like, but let me try. Imagine you're at a basketball game. The ref makes a call. Half the crowd thinks the ref is right, they're cheering. Other half thinks the ref is wrong, and they're booing. Imagine that for several hours.
DALLAS FOWLER: Oh, man, all day it's been everything from lock her up, to stop TPP, ban fracking, this is what democracy looks like.
SANDERS: Dallas Fowler is a Sanders delegate from California. And she says last night, Sanders supporters were yelling stuff like that.
FOWLER: Chants of noes. I - some of them were even saying no to the unity part, which was kind of like, OK, well, we actually work together on that.
SANDERS: Fowler said people should be allowed to speak their minds, but she wanted everyone to do it respectfully. During Michelle Obama's very well-received speech last night, such behavior was not tolerated. When a young Sanders supporter refused to stop heckling the first lady, this happened.
(SOUNDBITE OF ARCHIVED RECORDING)
UNIDENTIFIED WOMAN: Don't disrespect Michelle. Don't disrespect Michelle. Shut up.
SANDERS: This cycle of anger and indignation, boos and cheers - it went on for a while, but it did get better as the night went on. Many Sanders supporters I talked to said they're holding on for something, maybe for Hillary Clinton to say some words that put them at ease. Mary Anne Cummings, a Sanders delegate from Illinois, she was having a hard time explaining to me exactly what she wants to hear from Clinton.
What could she do to satisfy you?
MARY CUMMINGS: I would - it would be hard for me to know what she could say, but she would have to be convincing.
SANDERS: Cummings said, maybe Clinton could promise to forgo corporate donations to start. Another Bernie Sanders delegate, Jamie Friend of Florida, she told me last night that she wants a challenge on the floor during tonight's delegate vote.
JAMIE FRIEND: Well, we're going to have a roll call, and Hillary will not win the nomination on the first ballot. The superdelegates do not vote the first round. Correct?
SANDERS: Not correct. Actually, superdelegates do vote in the first round, and Hillary Clinton is almost certain to win the nomination. It's important to remember that the Bernie Sanders supporters inside the arena, they don't reflect how all of his supporters are feeling now. In fact, a lot of polls show that most Bernie Sanders supporters are getting comfortable with the idea of voting for Clinton. Today, I talked with one who wasn't in the arena last night, but watched it all go down on TV.
MIKE SCHAEFER: It didn't - it didn't sound good, certainly outwardly.
SANDERS: That's Mike Schaefer, Bernie Sanders supporter and Philly resident. He says, he gets it. This has been a campaign full of passion on all sides. And he points out some of the divisions he saw on the floor last night. They exist in his own family.
SCHAEFER: I live with one. My wife is a die-hard Hillary Clinton supporter, my mother is. We've had some back-and-forth on it.
SANDERS: Schaefer says his wife, the Clinton supporter, she was really upset by what she saw last night. But for what it's worth, he and his wife - they're still together. Sam Sanders - no relation - NPR News, Philadelphia.
CORNISH: You can hear more of Sam and get daily updates from the convention on the NPR politics podcast. Transcript provided by NPR, Copyright NPR.