Ms. James also said she had recently switched her own registration to that of the Working Families Party.
Democrats hope Mrs. McCarthy will formally switch her registration to their side.
"I switched my registration not out of convenience but out of conviction," Watts later recalled.
The former Mayor who dominated this city's politics a decade ago recently switched his registration to Republican.
He switched his registration after he won.
On May 29, 2013, he announced he was switching his registration to the Democratic Party.
In January 2008 however, she switched her registration to her adopted country.
Or I will start thinking about switching my registration to another agency.
"I switched my registration to vote for you," an elderly lady whispered to him.
She switched her registration from Democratic to "blank" or unaffiliated.