Despite another round of primary losses on Tuesday, Sen. Bernie Sanders said he is remaining in the presidential race, keeping the Sunday debate in Phoenix on track.

In words that challenged former Vice President Joe Biden to join him on the issues that have resonated with Sanders' base, the independent from Vermont said he is "very much" looking forward to their first head-to-head debate in Phoenix.

"It is not just the ideological debate that our progressive movement is winning. We are winning the generational debate," Sanders said in remarks to reporters in Burlington, Vt.

"While Joe Biden continues to do very well with older Americans, especially with those people over 65, our campaign continues to win the vast majority of the votes of younger people.

"Today, I say to the Democratic establishment, in order to win in the future, you need to win the voters who represent the future of our country and you must speak to the issues of concern to them. You cannot simply be satisfied by winning the votes of people who are older."

His decision comes as his path to winning the delegates needed to secure the Democratic nomination narrowed further and raises the stakes for Sanders in the debate at the Arizona Federal Theatre.

Rep. Ruben Gallego, D-Ariz., told The Arizona Republic after Sanders' press conference: "Now more than ever, the eyes of the country will be on Phoenix. This debate is happening because Arizona is crucial in November to stopping Donald Trump."

As it is, the first head-to-head debate with Biden comes just two days before voting ends in Arizona’s March 17 presidential primary and after many voters have already cast their ballots.

Sanders lost Arizona’s primary in his 2016 campaign by 15 percentage points to former Secretary of State Hillary Clinton, the eventual nominee. Florida, Illinois and Ohio, all states Sanders also lost in 2016, are holding their primaries Tuesday, too.

Sanders posted lopsided losses in Michigan, Missouri and Mississippi, and less than a week after holding a campaign rally at Veterans Memorial Coliseum in Phoenix.

His decision solidifieplans for a debate that Democrats hoped would show the party’s deepening commitment to Arizona. Regardless of Sanders' plans, the state seems poised to enter the next phase of the presidential campaign as a battleground.

President Donald Trump won Arizona in 2016, but by 3.5 percentage points, the narrowest margin since Bob Dole lost the state in 1996.

The Phoenix debate will be different from the 10 earlier Democratic debates in a few important ways.

On Tuesday, CNN, one of the media partners hosting the debate, announced that the event would not have an audience amid growing concerns about the spread of the new coronavirus.

For the same reason, organizers also eliminated plans for a room where campaign surrogates meet with reporters after the event to help shape the way the debate is cast in the media.

Reach the reporter Ronald J. Hansen at ronald.hansen@arizonarepublic.com or 602-444-4493. Follow him on Twitter @ronaldjhansen.

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