5 things to watch in Tuesday's New York primary

Here are five things to watch for in the primaries:

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1. GOP fight for delegates: There are 95 delegates at stake for Republicans in New York, and GOP front-runner Donald Trump wants to win all of them. He is polling high in New York, and a big win here helps him get closer to the 1,237 delegates he needs to clinch the nomination. If he can win 50 percent in the 27 congressional districts across the state and get 50 percent of the statewide vote, it is possible for Trump to sweep the delegates. If Trump gets less than 50 percent in a congressional district, the second-place finisher can pick up a delegate. That could give Ohio Gov. John Kasich a few to add to his column. In every recent poll since April 10, Trump is polling around 54 percent compared to a high of 25 for Kasich and 21 for Texas Sen. Ted Cruz. Cruz and Kasich hope to keep Trump below 50 percent in the congressional districts to keep him from sweeping the delegates.

>> WEIGH IN: Who will win New York's Republican primary?

2. Battle of New Yorkers: On the Democratic side, Sen. Bernie Sanders, who was born in Brooklyn, and Hillary Clinton, the former senator from New York, are going at it for the state's 291 Democratic delegates. Polls show Clinton up big in New York, and if that holds, it makes Sanders' path to the nomination more difficult. However, the polls are getting tighter. The Sanders camp is hoping for a Michigan-like come-from-behind victory, but the rules in New York make that less likely. Sanders said the polls aren't accurate in New York.

“Generally speaking, polling has underestimated how we do in elections,” Sanders said Monday on the "Today" show on NBC. It is true that Sanders sometimes closes the gap with Clinton in the polls as elections near.

In New York, 44 of the Democratic delegates are superdelegates who can vote for either candidate. The other 247 are divided up, with 163 awarded at the congressional district level. Eighty-four delegates are given out based on statewide results.

>> WEIGH IN: Who will win New York's Democratic primary?

3. Impact of a closed primary: The closed primary system will help Clinton. Unlike Ohio, which is an open primary where voters can change parties on election day, New York is a closed primary where voters have to vote in the primary of the party on their registration card. Not only do they have to stick with the party on their registration, they had to register in October. That could be bad news for Sanders. New York is one of only 11 states with this system. The closed system tends to affect young voters and independents, two groups key for Sanders.

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4. The Kasich effect: For Cruz, having Kasich in the race in New York may work to the Texas senator's advantage. Cruz, who is popular in heavily evangelical, conservative states, doesn't have a brand of politics that plays well in New York. He's running third in all of the polls there. Kasich will pick up delegates if he can keep Trump below 50 percent in a lot of the congressional districts. That could deal a blow to Trump even if Cruz has a bad night. Trump needs to win about 80 of New York's 95 delegates to stay on track of winning the nomination before the convention. Kasich could play a spoiler role here if he can pick up about 15 of the state's delegates.

5. Statewide polls are useless in New York: Trump will win New York, but those congressional districts are where the fight is. That's why you've seen Kasich campaign in places like Plattsburgh, N.Y., near Vermont, where he hopes to keep Trump below the magic 50 percent for that congressional district. If he is below that statewide or in most of the districts, it could kill his chances of winning enough delegates before the convention.