Sunday: Bernie Sanders, John Kasich, and new 2016 polls

Democratic U.S. presidential candidate Bernie Sanders arrives to speak during an election rally in Erie, Pennsylvania, U.S., April 19, 2016.

REUTERS/Lucas Jackson - RTX2APRX

Frontrunners Donald Trump and Hillary Clinton won big in the New York primary this week - can their rivals stop them, or is it too late? This Sunday on "Face the Nation," we'll look at the state of the 2016 election as the primary calendar heads into the homestretch.

We'll talk with Vermont Sen. Bernie Sanders, who has vowed to continue fighting for the democratic nomination even as his path narrowed considerably after losing New York. How does he hope to pull out a victory, given the daunting delegate math? Is he prepared to take the fight to the convention, no matter what?

Turning to the Republican race, we'll talk with Ohio Gov. John Kasich, who continues to trail both Trump and Texas Sen. Ted Cruz in the race for GOP delegates. What is Kasich's goal for the remaining handful of contests? And how does he believe a contested convention could work to his advantage?

We'll get a new set of CBS News Battleground Tracker polls on the race in both parties in Pennsylvania, which votes next Tuesday, and Indiana, which votes May 3. CBS News Elections Director Anthony Salvanto will join us to analyze those numbers and the path forward in each party.

We'll also talk with the New York Times' Mark Landler about his new book, "Alter Egos," a deeply-reported examination of the foreign policy crafted by President Obama and former Secretary of State Hillary Clinton.

And as always, we'll convene an expert political panel to help us break down the busy news week, including Reihan Salam of the National Review, Ezra Klein of Vox, Ed O'Keefe of the Washington Post, and CBS News Congressional Correspondent Nancy Cordes.

It's going to be an exciting broadcast, so make sure you tune in! Check your local listings for airtimes.