We are just two days away from NY1's Democratic primary debate in the mayor's race. And despite his lead in the polls and in fundraising, Mayor de Blasio says he is preparing as if he were the underdog. Our Grace Rauh has the story.

Don't let his August vacation fool you. Mayor de Blasio insists he is taking Wednesday's Democratic primary debate on NY1 very seriously. He will face off against former City Councilman Sal Albanese, who is running for City Hall for the fourth time.

"I have been preparing," the mayor said. "I have been doing a number of prep sessions already. I have been an underdog in essentially every race I have ever been in. This is a different dynamic but it doesn't change my preparation.

So far, de Blasio has largely ignored his Democratic rival as he runs for a second term. But it will be hard to do that Wednesday, when he faces only Albanese on the debate stage.

Instead de Blasio has been taking aim at his Republican opponent, Staten Island Assemblywoman Nicole Malliotakis. She spent Monday visiting public housing developments around the city.

"What I'm hearing is that New York City is the biggest slumlord in the city of New York," Malliotakis said.

Meanwhile, there has been some debate about the debate and who made the cut.

There are very clear rules about how you qualify and they aren't that onerous in the scheme of things.

Candidate Mike Tolkin says he should have been invited to participate after meeting the Campaign Finance Board's threshold to join. He is not participating in the campaign finance program so it was up to debate sponsors - including NY1 - to decide whether to include him. In a statement explaining its decision, NY1 noted that Tolkin has not had a visible presence on the campaign trail.

"I've been hitting the streets in a different form, which is a quiet listening capacity," Tolkin said.

Another Democratic candidate, Richard Bashner, is suing the Campaign Finance Board and NY1's parent company over his exclusion from the event. He says the normal debate requirements should be waived because there are so few candidates in the race.