Clinton remains favored in New York's April 19 primary. A victory in the state that twice elected her to the U.S. Senate would blunt Sanders' momentum argument. And his only remaining chance for the nomination is stringing together a series of solid, lopsided victories that narrow her lead among pledged delegates and generate a collapse in confidence among unpledged "super delegates" who overwhelmingly favor her so far.
At the same time, Republican polls have shown Trump with an enormous lead in New York state, large enough that he can win the vast majority of the 95 Republican delegates at stake. If he can do the same the following week in Maryland, Connecticut, Rhode Island, Pennsylvania and Delaware, he can halt Cruz's momentum and pull close to the delegate majority he needs.