I think there are stronger ex-NYPD candidates out there than Kerik. Timoney from Miami is ex-NYPD, along with Bill Bratton who is currently running the LAPD. Talking to many NYPD officers and supervisors with a lot more experience leads me to believe that there are quite a few others just from our department that are even better qualified than Kerik.
Kerik became nationally known after his work on 9-11. That doesn't mean that there aren't other well-qualified NYPD candidates along with many others from other law enforcement agencies with whom I'm not acquainted. Honestly, I never heard anything positive about Kerik other than he was a decent street cop and didn't destroy the innovative projects of his predecessors.
I'm not sure of the politics involved, but from what I've heard and experienced I'd be talking to Mr. Bratton right now.