More than just Philadelphians have an interest in who will replace Mayor Nutter in City Hall in 2016. The Democratic National Committee has been asking about the coming mayor's race as well, according to U.S. Rep. Robert Brady (D., Pa.).

Chiefly, the committee needed an assurance that the next mayor will want the Democrats to bring their 2016 convention here as badly as the current holder of the office does.

Brady, as part of the city's latest sales pitch to the DNC, offered an unqualified yes.

"I told them that anybody who wants to be mayor in this town has to come through me at least a little bit, and I've talked to every major potential candidate," he said Monday. "And they are all, 100 percent, all in."

And if Brady's word was not good enough, Philadelphia's boosters went a step further. They got pledges from announced mayoral candidates - there are five so far - and did not stop there.

"We gave them letters from every conceivable mayoral candidate, Republican and Democrat," said former Gov. Ed Rendell, "saying they would honor the commitments made by the Nutter administration."

The assurance was offered two weeks ago when a contingent that included Brady, Nutter, Rendell, U.S. Sen. Robert P. Casey (D., Pa.), and U.S. Rep. Allyson Y. Schwartz (D., Pa.) met in Washington with DNC members to press the city's case for hosting the party's next presidential nominating convention.

On that day, Dec. 18, the DNC heard from representatives of each of the finalist cities - the others being Columbus, Ohio, and New York City.

"The main thing was money. They wanted to be sure we could raise money," said Brady, who is the city's longtime Democratic party chairman.

To that end, Philadelphia was able to show it had already lined up $5 million from contributors, he said.

Rendell said the city will all but double that figure when it submits its final bid Jan. 14.

"I just signed the papers this morning," Rendell said Monday. "It is our final proposal, which has the effect of being a contract, and we will put nearly $10 million in an escrow account, which is what they ask from us. If we don't get the convention, the money goes back, dollar for dollar, to the people who gave it to us."

The Philadelphia committee put the hard sell on potential donors in November, when it brought together about 25 well-heeled party supporters and asked for their help.

Among those in attendance were Daniel Hilferty, chief executive of Independence Blue Cross; John Fry, president of Drexel University; Harold Honickman, chairman of the Honickman Group; Thomas A. Leonard, chairman of the law firm Obermayer Rebmann Maxwell & Hippel L.L.P.; and Christina Lurie, a part-owner of the Eagles.

Potential donors were said to be extremely enthusiastic.

"Every pledge I got told me they would double or triple it as soon as we knew we had the convention," Brady said. "People wanted to give more, but we tried to get most of the donations in $25,000 increments to show how many donors we had."

Rendell was cautiously optimistic when asked to assess the city's chances. He noted the importance of Ohio in recent presidential elections - a factor that helps explain why the Republican Party is holding its 2016 convention in Cleveland - as well as Pennsylvania's pattern of going for the Democrats' national ticket in recent decades.

"I feel good, although our two competitors both have things that recommend them," he said. "New York, of course, is the safest bet in terms of raising money and not leaving the DNC with any debt. And Columbus has the great asset of being in the ultimate swing state. I sometimes worry that because we have won five straight presidential elections, we are thought of more as a blue state than a swing state."

A final selection for the DNC convention is expected late January or early February, he said.