Sen. Bernie Sanders (I-Vt.) is remaining in the Democratic presidential primary, despite acknowledging Wednesday that he is losing to former Vice President Joe Biden in the delegate count and has failed to convince millions of voters that he is more electable against President Donald Trump.

Sanders said he was looking forward to facing off against Biden in the next presidential debate on Sunday and said he believes he is winning in two key areas: support for a progressive agenda and backing from young people.

“On Sunday night, in the first one-on-one debate of this campaign, the American people will have the opportunity to see which candidate is best positioned to accomplish that goal,” he said.

Biden and Sanders are set to debate Sunday night in Phoenix, Arizona, a state that will vote next Tuesday. There will be no live audience and no press area, due to the coronavirus outbreak.

Sanders pointed to concern over income inequality, support for corporations to pay their fair share of taxes, and a higher minimum wage as areas where the public supports what he is proposing.

“Poll after poll, including exit polls, show that a strong majority of the American people support our progressive agenda,” Sanders said.

Sanders continues to get significantly more support than Biden from young voters, and he argued that the Democratic Party needs to try harder with this demographic.

“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,” he said.

Sanders did not vow to stay in for the long haul, and his comments indicated that he sees the writing on the wall. While he’s still trying to make a last-ditch attempt to convince voters to choose him, he also is clearly trying to push Biden to adopt some of his more progressive policy proposals.

He said that at the debate, he will push Biden on issues including Medicare for All, climate change, college affordability and debt, immigration, childhood poverty, high health care costs, and “the absurdity of billionaires buying elections.”

Sanders pulled out victories in the first three voting states, but since then, Biden has outperformed him, especially in states with large Black voter bases. Sanders lost significantly to Biden in South Carolina and underperformed on Super Tuesday, even though Biden barely had any infrastructure in place in most of those states.

On Tuesday, Biden won nearly every state, including Michigan and Idaho, states that Sanders won against former Secretary of State Hillary Clinton in 2016. Sanders canceled his rally in Ohio on Tuesday night due to coronavirus concerns ― as did Biden ― but unlike Biden, Sanders did not make any public remarks.

“Last night, obviously, was not a good night for our campaign, from a delegate point of view,” Sanders acknowledged on Wednesday.