Andrew Cuomo and Mark Green, and perhaps others, will be squaring off in the 2006 Democratic primary for state attorney general. Robert F. Kennedy Jr. declined to enter the race, and now the Republicans see the seat Eliot Spitzer is vacating as a prime target for their candidate. The question is, who will that be?

The rumor mill has been churning out the names of the Westchester district attorney, Jeanine Pirro, who is very popular among Fox News watchers, and a state senator of Nassau County, Michael Balboni. I’ve never met either of these potential candidates, but there are those who believe we have a very viable candidate right here in New York City: Daniel Donovan, the new Staten Island D.A.

He hasn’t made any formal announcement. In fact, it was only a rumor that made me seek an interview with the busy prosecutor, to pin down the gossip about his possible run. Mr. Donovan has been the district attorney for only a year and is enjoying the job very much, he said, but he was noncommittal about running for attorney general.

There have been quite a number of positive changes in the district attorney’s office since his election, and one of his biggest boosters is his former boss, Guy Molinari, the former borough president. Mr. Molinari once ran for district attorney and is familiar with the problems that existed within that department. In just the one year since Mr. Donovan came on board, Mr. Molinari told me, there’s been a remarkable improvement.

“Dan’s done a terrific job as the district attorney. What is unbelievable is that he’s done it with the same people who were there before,” Mr. Molinari said. “I’ve specialized in recruiting many candidates over the years, between 50 and 60, including John McCain,” he continued. “I have never felt higher praise for anyone as I feel for Dan Donovan. He was my chief of staff for six years and he was unique. He has the ability to handle any issue and run with it. He was the chief negotiator with the Giuliani administration over the Fresh Kills landfill closing.” Mr. Molinari was on medical leave at the time, he said.

Mr. Molinari’s enthusiasm for his former chief of staff was evident during our conversation, and when he said “everybody likes Dan,” he wasn’t being overzealous. Mr. Donovan does enjoy a good working relationship not only with his staff but with police officers as well. The New York State Shields, a police fraternal association, named him Person of the Year in 2004 for service to law enforcement. He was elected third vice president of the New York State District Attorneys Association two weeks ago at the group’s winter conference .

So Mr. Donovan’s a popular guy. He may even be a great guy, but would he make a great attorney general? One would have to look at his record to make that determination. His office leads the city in the rate of felony convictions; led the city in 2004 in the conviction and incarceration of Megan’s Law violators, and obtained the first felony conviction in the state under Stephanie’s Law, targeting video voyeurs.

Several notorious cases that had been open for years were finally settled last year. His prosecutors nailed an alleged drug enforcer for the 1987 slaying of a West Brighton woman. They convicted Andre Rand of the 1981 kidnapping of Holly Ann Hughes. Rapists, killers, bias criminals, drunk drivers, even graffiti vandals were dealt with swiftly.

Daniel Donovan learned from the best. After all, he was an assistant district attorney to Robert Morgenthau, Manhattan’s D.A., who is widely regarded as one of the nation’s best prosecutors. All this may be very impressive, but how smart have the Republicans been in fielding candidates in this state? Their recent record is abysmal. Will they go for Ms. Pirro, who is an attractive and telegenic candidate but carries the baggage of her husband’s tax-evasion conviction? Mr. Balboni is … who?

There is another factor to consider. Eliot Spitzer used his position as A.G. to target pregnancy-crisis centers that offered alternatives to abortion. Pro-choice advocates contributed significantly to his campaign. Mr. Donovan, I’ve been told by admirers, would be more independent.

“Dan is a very compassionate guy,” Guy Molinari said. He illustrated that with an anecdote that I’m sure Mr. Donovan would not want me to repeat in public. But I didn’t need any convincing. I’ve witnessed his successful interaction with victimized Mexican immigrants. Most striking to me was the sight of a photograph he keeps near his computer keyboard of little Holly Ann Hughes.

Mr. Donovan may be a compassionate man, but when it comes to catching criminals, he is all business.