WASHINGTON — On April 19, Governor Spitzer called for the eventual shutdown of a nuclear power plant 24 miles from New York City, saying it’s “not a smart location” for a facility he has warned is vulnerable to a terrorist attack.

That assessment was a setback for one of the Indian Point plant’s biggest boosters: Mayor Giuliani. Mr. Giuliani, whose consulting firm advises plant owner Entergy Corp. on security and evacuation plans, last November declared the company a “model” of safety.

Indian Point is one of several projects Mr. Giuliani has pushed for corporate clients that may clash with his image as a homeland-security expert, a reputation he won as New York’s mayor during the September 11 attacks that killed more than 2,900 people.

Some of those associations may haunt him, says Richard Clarke, the White House counterterrorism chief during the 2001 attacks, when hijackers crashed airliners into the World Trade Center, the Pentagon and a field in Pennsylvania.

“You have no obligation to take on security assessments for people who have insecure facilities,” says Clarke, who served on the National Security Council under both Presidents Clinton and Bush. For a candidate, “there is a risk that somewhere in your client base something will go very, very wrong.”

Mr. Giuliani, 62, is also advising TransCanada Corp. and Shell Oil Co. on a plan to place a 1,215-foot-long barge on Long Island Sound to store liquefied natural gas. Connecticut’s Governor Rell, a Republican, is among those opposing the project on safety grounds.

His law firm has lobbied to exempt respiratory-mask manufacturers from lawsuits when equipment fails, a position that has outraged police and firefighters. The firm also represents an oil company controlled by Venezuela’s President Chavez, who has challenged U.S. influence throughout Latin America.

Mr. Giuliani, who leads the race for the Republican nomination in every major poll, and his campaign didn’t respond to questions about whether his business relationships may become an issue.

Rep. Peter King of New York, a Giuliani supporter and the top Republican on the House Homeland Security Committee, says the candidate has already established his credibility on public-safety matters. “Rudy is expecting to be attacked on everything,” Mr. King said. “I think he’s prepared. He knows what the stakes are.”

The former mayor has taken steps to reduce his involvement in business, saying he will leave his New York-based consulting firm, Mr. Giuliani Partners LLC, and selling his investment bank, Giuliani Capital Advisors LLC, to Macquarie Bank Ltd. of Sydney. He remains a partner in the Houston-based law firm of Bracewell & Giuliani LLP.

Last month, Mr. Giuliani’s law firm said he wasn’t involved in its lobbying on behalf of Citgo Petroleum Corp., the company controlled by Mr. Chavez’s Venezuelan government.

The Indian Point nuclear plant, perched on the Hudson River north of New York City, has raised safety concerns throughout its 32-year history. Those concerns turned to alarm after the September 11 attacks, when a jet plane flew past the site minutes before crashing into the south tower of the World Trade Center.

James Lee Witt, a former head of the Federal Emergency Management Agency, said in a 2002 report that evacuation plans for the surrounding area were inadequate, a conclusion echoed by Democrat Mr. Spitzer, 47, when he spoke to reporters after an April 19 breakfast meeting in New York.

Indian Point has had at least eight emergency shutdowns since 2005. On April 15, the plant flunked a Nuclear Regulatory Commission Siren test, prompting the commission to recommend a $130,000 fine.

Mr. Giuliani’s consulting firm had recommended the Siren’s manufacturer, ATI Inc. of Boston, according to Jim Steets, a spokesman for New Orleansbased Entergy, the second-largest American operator of nuclear power plants.

On November 22, Mr. Giuliani backed Entergy’s application for a 20- year extension of its licenses, which expire in 2013.

“Indian Point is as safe as a facility can be,” he told reporters at the time. He said pursuing nuclear energy is one way that America can achieve energy independence. “There is nothing that produces energy that doesn’t carry risk,” he said. Mr. Steets, who says Entergy hired the candidate’s firm in 2003, says the company believed that Mr. Giuliani’s seal of approval “would go a long way in persuading people” the company had made the plant safe.

Richard Sheirer, a partner at the consulting firm who ran New York’s Office of Emergency Management when Mr. Giuliani was mayor, declined to comment on advice given Entergy.

Another Giuliani Partners client is Broadwater, the joint venture of Calgary-based TransCanada and Houston-based Shell that wants to store liquefied natural gas on Long Island Sound. The barge could supply Connecticut and New York with 1 billion cubic feet of LNG a day. Proponents say the project would reduce the costs of storage and transmission, and help spur economic growth.

Last month, a report by the U.S. Government Accountability Office, the investigative arm of Congress, said some studies estimate a terrorist attack on the facility could cause a fireball to extend across an area of more than 2.6 miles.