Sources told CNN that Cuomo's team believes the general electorate could be more receptive to his candidacy than primary voters.

The left-wing state Assemblyman has repeatedly cited one sitting mayor as a person whose time in office inspires him: None other than Boston’s mayor, Michelle Wu. In the first debate in that race, he went so far as to name Wu as the most effective Democrat in the nation. He has often cited her as a politician he would emulate.

Both candidates seek to remake Democratic politics in fundamentally different visions. But the Democratic mayor isn't running as a Democrat.