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A big crowd came out to see Bernie Sanders in New York last night. According to his campaign, it was 27,000 people. Judging by that, Bernie Sanders has plenty of support in next week's New York primary. But Sanders faces a challenge in New York which has to do with the rules under which he contends against Hillary Clinton. NPR's Tamara Keith explains.
TAMARA KEITH, BYLINE: It doesn't get more New York than this - the Empire State building glowing blue and green in the distance as Bernie Sanders took the stage in Greenwich Village.
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BERNIE SANDERS: There are a lot of people here tonight.
KEITH: In addition to everyone on the ground in Washington Square Park, people watched from nearby high-rises. Sanders spoke for an hour. The audience alternated between wild applause for Sanders and boos for the status quo and his opponent. But as he was winding down, Sanders told the crowd about a large challenge his campaign faces.
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SANDERS: And we have a system here in New York where independents can't get involved in the Democratic primary...
UNIDENTIFIED SANDERS SUPPORTERS: (Booing).
SANDERS: ...Where young people who have not previously registered and want to register today just can't do it.
KEITH: This is of particular concern for Sanders because independents are a key part of his coalition. He's performed best in open primaries and caucuses. But the New York primary is closed. New voters had to register as a Democrat last month to vote for Sanders. And voters who wanted to change their registration to the Democratic Party had to do it months ago.
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SANDERS: So it's going to be a tough primary for us. But you know what I think? When I look out at the thousands of people who are here tonight...
(CHEERING)
SANDERS: ...The thousands of people we saw in Buffalo and Syracuse and Rochester...
(CHEERING)
SANDERS: ...I think we've got a surprise for the establishment.
KEITH: Politico's Capital New York website reported that Erica Garner, an activist who stars in a Sanders campaign ad, likely won't be able to vote because she isn't registered with a party.
JEFF WEAVER: You know, it's a more challenging environment for us.
KEITH: Jeff Weaver is Sanders' campaign manager.
WEAVER: The date to switch party registration was in October, which seems, you know, quite early. So, you know, there will be a number of people, obviously, in New York who intend to come out to vote both, I think, for Secretary Clinton and for Sen. Sanders, who are going to come - try to come out and vote who are, you know, independents and are going to be disappointed, I think.
KEITH: But every Sanders supporter I interviewed at last night's rally said they had registered to vote as Democrats. Joanna Bardis and Smitha Barghese say they got excited about Sanders watching videos on YouTube.
JOANNA BARDIS: As soon as I saw that video, it just - my life changed. I didn't - I wasn't going to vote. I wasn't into voting for any president.
SMITHA BARGHESE: And this is our first time voting at all. We're 22. We've never voted. We never felt the need to - well, actually, I did want to vote for Obama. But I never got to.
KEITH: As the deadline to register approached, both went on social media and encouraged their friends to get signed up before it was too late. Tamara Keith, NPR News, New York. Transcript provided by NPR, Copyright NPR.
