Supporters of Howard Dean saw their candidate’s front-runner status crumble after his infamous “I have a scream” speech following the Iowa Democratic caucuses of January 2004. With the attorney general of New York, Eliot Spitzer, leading all potential challengers in the 2006 governor’s race, his supporters might want to pause and ask if Mr. Spitzer has similar temperamental problems.

Mr. Spitzer has won scores of settlements with some of the nation’s shrewdest corporate executives largely through hardball negotiating tactics. One does not earn the nickname “The Sheriff of Wall Street” without twisting a few arms. Yet a growing body of evidence suggesting that Mr. Spitzer’s intensity verges, at times, on thuggery has left some of the attorney general’s political adversaries waiting for a Dean-like eruption to use against him in next year’s race. “This guy just doesn’t have the temperament to be governor,” the executive director of the Republican State Committee, Ryan Moses, said. “He’s doesn’t know how to deal with people.”

Some notable blowups have already occurred. The best known, perhaps, took place at a meeting of the National Association of Attorneys General in California a couple of years ago. According to New York magazine, Mr. Spitzer asked another attorney general at the event if wanted “to step outside” during a heated argument. “That’s fine,” Mr. Spitzer is reported to have shouted, adding: “I grew up in the Bronx.”The story made the rounds then because Mr. Spitzer grew up in the affluent Riverdale section of the Bronx and attended the prestigious Horace Mann college preparatory school there. It is being revived now as reports of similar confrontations have begun to circulate.

One such recent flare-up took place at last year’s Democratic National Convention in Boston, where Mr. Spitzer is said to have run into a former chief executive of General Electric, Jack Welch, and asked him to pass along a message to Kenneth Langone. Mr. Langone is a founder of Home Depot who is being pursued by the attorney general’s office for his role in setting a massive pay package for a former head of the New York Stock Exchange, Richard Grasso. A Newsweek account of the conversation had Mr. Spitzer saying he was so mad at Mr. Langone that “he’s going to put a spike through his heart.”

And this spring, Mr. Spitzer is said to have responded hotly to an opinion piece written for the Wall Street Journal by John Whitehead, the octogenarian financier and current head of the Lower Manhattan Development Corporation. The article was a defense of the former AIG chairman and chief executive, Maurice “Hank” Greenberg, who is also being pursued by Mr. Spitzer for alleged accounting fraud at the insurance giant. An aide to the attorney general, Darren Dopp, said that Mr. Spitzer called Mr. Whitehead to register his displeasure with the article. But Mr. Dopp denied the call was placed in a froth. “Mr. Whitehead wrote things that were absurd, and Eliot called him up to ask where he got the information,” Mr. Dopp said. “That’s not a temper.”

The call to Mr. Whitehead will come as no surprise to reporters and others who have leveled criticism against Mr. Spitzer. A prominent business reporter at Newsweek, Charles Gasparino, told the investor James Cramer on CNBC’s “Kudlow & Cramer” show last July that he got a call after suggesting that Mr. Spitzer erred in the case against Mr. Grasso by not going after a Democratic politician who sat on the compensation committee with Mr. Langone. “I really think not charging Carl McCall is political,” Mr. Gasparino said at the time. “Now the last time I said that, you know, I essentially got threatened by one of Eliot Spitzer’s p.r. guys. So their problem is you can’t disagree with them.”

Mr. Spitzer’s public relations guys defend their dealings with the press. Mr. Dopp said his critics would be hard-pressed to find an article from a major newspaper in which the attorney general’s office was said to have not returned a call. He described the California incident as “a spirited discussion” and the Newsweek story as “a hearsay account from a hallway conversation.” He characterized Mr. Spitzer as “a person of integrity” whose passion is sometimes confused with temper. “I’m sure Mr. Spitzer has had heated discussions in the past and will have them in the future,” he said. “But he should be judged on what he’s accomplished, not a bunch of rumors.”

The defenders of Mr. Spitzer’s aggressive prosecutorial and personal style like to argue that because the attorney general sets high ethical standards for himself, criticism of his integrity or character is out of bounds. Others, like the officials at the Republican State Committee, say those who set high standards invite scrutiny. Democrats tried to block John Bolton from becoming U.N. ambassador because of his temper, they say, and Mr. Spitzer should expect to face similar charges in the governor’s race. With Mr. Spitzer leading by double-digit margins in the polls, the temperament card may be one of the few hopes his opponents have against him. It is unlikely to be left unplayed.