The Democratic mayoral primary has been in full swing for months, with candidates participating in dozens of virtual debates and forums hosted by political clubs, community organizations and advocacy groups.

But tonight is different.

The city’s first officially sanctioned debate comes as many New Yorkers turn their attention to the race for the first time. It presents the largest virtual stage yet for candidates to make their case to voters, and to set themselves apart in a historically large group of viable contenders.

Here’s what to watch for:

Attacks on the frontrunner(s)

Entrepreneur and former presidential candidate Andrew Yang has dominated media coverage for the past few months and led in nearly every poll conducted up to this point. But if Yang is the frontrunner, Brooklyn Borough President Eric Adams is close on his heels. Expect them both to come under attack, especially given their moderate positions relative to the rest of the field.

Who will unite the left?

City Comptroller Scott Stringer has amassed the most support from the progressive left, but many of those supporters have abandoned him in the wake of an allegation of sexual misconduct. That has created space for two other candidates, civil rights attorney Maya Wiley and non-profit executive Dianne Morales. Watch to see if they go after Stringer – and try to claim the mantle of progressive champion.

A breakout moment?

Former Obama cabinet member Shaun Donovan, former Citi executive Ray McGuire and former sanitation commissioner Kathryn Garcia have struggled to get out of the single digits in polling. Tonight is their chance to make a splash and break out from the pack – with Garcia looking to capitalize on the momentum generated by her New York Times endorsement earlier this week.

A balancing act on policing

Public safety has become one of the most politically fraught issues of the campaign. Candidates have had to address a rise in gun violence – punctuated by last weekend’s Times Square shooting that injured three bystanders – while also speaking to issues of police accountability and taking a stance on defunding the police, the rallying cry that grew out of last year’s protests. Eric Adams, a former police officer, has been most vocal on the issue of tackling crime. Watch to see whether any of the candidates challenge him on the issue -- and how they navigate the tightrope themselves.