Knox had toyed with the idea of a primary challenge and also considered sitting on the sidelines in support of former mayoral candidate Sam Katz or City Councilman Bill Green.
Katz says he won't run.
Green and state Sen. Anthony Hardy Williams are enjoying the attention of Nutter foes urging them to put up a challenge, but so far they appear unlikely to do so.
Knox is keeping much of his strategy under wraps but says an independent run allows him to reach out to Democrats, Republicans and independents.
"There will be a lot more people who can vote," Knox said.
How many? There were 1,013,876 registered voters in Philadelphia as of Monday - 798,211 Democrats, 126,855 Republicans and 88,810 independents.
The only Republican running for mayor so far is John Featherman, a real-estate agent who has unsuccessfully run for Clerk of Quarter Sessions, the U.S. Senate and the U.S. House.
Featherman seems as eager to battle the old guard of the Republican City Committee as he is to take on a Democrat in the fall.
Knox is likely to trigger the "doubling provision" of the city's campaign-finance law, which means that individuals can contribute twice the $2,600 limit ($5,200) and $10,600 ($21,200) for political-action committees if a candidate puts more than $250,000 of his own money into an election.
Knox triggered that provision in his 2007 primary run.
There is one drawback to running as an independent: Knox will have to gather nearly twice the nominating-petition signatures.
Democrats and Republicans need 1,000 signatures by March 8 for a spot on the primary ballot.
Knox needs signatures matching 2 percent of the votes for the last citywide election winner.
That would be District Attorney Seth Williams, who got 92,273 votes in 2009.
So, Knox needs 1,845 signatures by Aug. 1 to land a spot on the general-election ballot.
Knox, who wants to call himself an "independent Democrat," will also have to "disaffiliate" from the Democratic Party at least 30 days before the primary to run for mayor as an independent.
Will Deeley have Senate help?
Barbara Deeley was nominated this week as the city's first female sheriff. But she faces a tough time in the state Senate confirmation process, and it is not clear whether any of Philadelphia's senators will go to bat for her.
Deeley would take over for her boss, Sheriff John Green, as his office is under heavy scrutiny from the City Controller's Office for the potential mismanagement of millions in public dollars.
Gov. Rendell sent her name to the Republican-controlled state Senate just as he prepares to hand over control to Gov.-elect Tom Corbett, a Republican.
Corbett could recall Deeley's nomination and then make his own pick for the post.
So what do the city's seven state senators think?
State Sen. Vincent Hughes said that the timing of the nomination means that the pick "becomes the call of the next governor."
Williams said that Rendell gave no notice of the nomination, so the senators from the city are "not in a position to defend it, advance it or protect it."
State Sen. Larry Farnese said that he needs to know more about Deeley before he decides if she's the right person to run the office, in light of the pending controller audit.
State Sen. Mike Stack, through a spokeswoman, voiced support for Deeley but did not grant our request for an interview.
State Sens. Shirley Kitchen, Christine Tartaglione and Leanna Washington didn't respond to questions about Deeley.
Ed loves the press, a payday
PhillyClout had to dab away the tears when Rendell held his final news conference in Philadelphia as a public official this week.
Rendell praised the press, while acknowledging that he hasn't always enjoyed our attention.
"As irritated as I get at times, I always remind myself this is the way that democracy was intended to work," Rendell said. "If our Founding Fathers could come back to Earth in this electronic age, I think they'd be basically proud of what we have done and the communications level we have."
Speaking of the electronic age, Rendell said that he had no news to report on his hunt for a cable-news- pundit gig but declared this:
"The next time you hear me speak in Philadelphia, somebody's going to be paying for it."
It probably will be a nice salary, too. Rendell finally confirmed what we told you seven weeks ago - that he has signed on with William Morris Endeavor Entertainment, in Beverly Hills.
The firm has represented former U.S. Secretary of State Condoleezza Rice, former U.S. House Speaker Nancy Pelosi and former U.S. Sen. Fred Thompson, an actor in NBC's "Law & Order" who ran for president.
Rendell said that he signed with the firm because of its experience with television, pushing autobiographies and setting up speaking engagements - three lucrative lines of work in his near future.
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