The deadline for cities to express an interest in hosting the convention is Saturday.
On Thursday morning, Nutter did send a letter to Wasserman Schultz, lauding the city's "rich history, cultural vitality, diverse communities" as "an ideal backdrop" for the convention.
But the letter didn't go out before this latest rift between the city's political titans was exposed.
On Thursday morning, City Councilman James F. Kenney said he feared Nutter wouldn't follow through - so he introduced a resolution expressing Council's interest in bringing the convention here.
When a copy of Nutter's signed letter to Wasserman Schultz made its way to Kenney on the floor of Council, he joked that the paper was "still warm." He said it was "likely" his resolution forced the mayor's hand.
"Every indication we had been getting through back channels was, things were slowing down, if not stopping," Kenney said. "To me, I don't know what would take so long to say, we're interested."
Brady said that he called Nutter about the deadline on Wednesday and that Nutter promised "to look at it in the morning."
"I really hope the resolution didn't force him to do it," Brady said. "I hope he really wants to do this."
Mark McDonald, the mayor's spokesman, called the whole matter "a tempest in a teapot" and said Nutter was "well aware of both the process and the deadline."
"We did what we intended to do," McDonald said. "This is clearly playing politics with politics."
While a convention promises to be a huge economic boost - Brady said it would be worth as much as $300 million to the local economy - it also brings headaches, costs, and disruptions. Because of security, the 2012 Democratic convention virtually closed off downtown Charlotte, the North Carolina host city.
Philadelphia last hosted a party convention in 2000, when Republicans gathered here to nominate George W. Bush. The Democrats last met here in 1948.
Federal filings after the 2000 convention showed regional taxpayers forked over nearly $39 million to cover expenses.
Brady has said tax dollars may not be needed this time, partly because of federal security grants. He also said a nonprofit would have to be formed to raise up to $40 million.
He said hosting the party would be "great for the city on every level."
"If [Nutter] tells me that he's 100 percent for it, then he's 100 percent for it," Brady said. "It's his show. He's the mayor. . . . I'll give him the support he needs."
Also during Thursday's Council meeting, Councilwoman Maria Quiñones Sánchez fired the opening salvo in the coming battle over school funding.
She introduced a bill to increase the school's split of property taxes from 55 percent to 60 percent, worth about $53 million more to the schools.
"It should be part of the conversation," she said.