On the eve of his stint in federal prison, in 2002, colorful former Providence mayor Vincent A. “Buddy’’ Cianci Jr. famously looked ahead to his sentence as an opportunity to quit smoking and maybe drop a little weight.

“It’s like going to a very inexpensive spa,’’ he cracked, before spending nearly the next five years behind bars at Fort Dix, N.J.

The charismatic politician who repeatedly resurrected his professional career from personal failings and criminal convictions died Thursday. He was 74 and had been treated for cancer.

Known for his electric wit, sharp tongue, and the salt-and-pepper toupee he eventually discarded, Mr. Cianci was an architect of the downtown Providence renaissance, a remaking of what the Los Angeles Times once dubbed a “dreary little mob town’’ into an upscale theater and dining district, known for the performing arts, an expansive retail mall, and cafes along new riverwalks.

“Buddy was the best mayor Providence ever had at performing the job of mayor,’’ said Ray Rickman, a Rhode Island civic leader and former state representative. He mentioned Mr. Cianci alongside Thomas Menino and Kevin White — “great mayors of Boston who moved the city forward — and Buddy did a lot of that.’’

For four decades, Mr. Cianci was a dominating personality in Providence politics. It seemed no public event was too obscure for his attendance when he was in office, and he seemed to enjoy jousting with his opponents and the media.

A mercurial master of one-liners and political barbs, he could go from one emotion to another in an instant, said Mike Stanton, a former Providence Journal reporter and author of “The Prince of Providence,’’ a biography of Mr. Cianci.

“You never knew what you were going to get with him but it was usually memorable,’’ Stanton told the Globe. “He was friendly, intimidating, brusque, funny — but he was always something.’’

Mr. Cianci’s criminal convictions, including one for public corruption, have long confounded supporters and critics: How could such a smart and gifted politician have done things so profoundly stupid?

“I believe when you hold office long enough you begin to think you make your own rules,’’ Rickman said. “A moral compass and fear — you need both and I don’t know how much fear Buddy had.’’

Originally elected as a good-government reformer, Mr. Cianci was mayor from 1975 to 1984, an era known in Providence as Buddy I, and again from 1991 to 2001, known as Buddy II.

Buddy I ended when Mr. Cianci pleaded no contest to attacking his estranged wife’s alleged lover with an ashtray, lit cigarette, and a fireplace log. He was given a suspended sentence and was forced to resign. He stayed in the public eye as a radio personality, and then defied political prognosticators in his 1990 comeback, winning the mayor’s job again, this time by a few hundred votes in a three-way race decided by a recount.

His closest opponent in that race, Fred Lippitt, said in his concession remarks that Mr. Cianci had “great talent — if he can put it to good use. Not everyone is given a second chance and this time I hope he really will be different.’’

But Buddy II ended after Mr. Cianci was indicted in 2001 for allegedly orchestrating bribes for jobs, contracts, and contributions to his campaign fund. The FBI investigation into City Hall corruption was code-named Operation Plunder Dome. He was eventually convicted of one count of racketeering conspiracy and sent to prison, getting out in 2007.

After his time away in what Mr. Cianci called a “gated community,’’ the former mayor returned to the radio as a talk show host — with a break for one more run for mayor in 2014, which he lost.

Earlier this month, Mr. Cianci announced he was engaged to Tara Marie Haywood, who is described in media reports as being in her 30s.

Mr. Cianci formerly was married Sheila Bentley. They later divorced, and the only child from their marriage, Nicole Cianci, died in 2012, leaving three children.

Many in Providence fondly recalled the former mayor Thursday. Rose Weaver, a Rhode Island singer and actress, on Thursday called Mr. Cianci a “visionary’’ who believed in the power of the arts to improve a community.

Choking up with tears, she said the city’s major arts institutions — the Providence Performing Arts Center, Trinity Repertory Company, and the downtown gallery and performance venue AS220 — “survived because of his impact. Providence is what it is today because of Buddy Cianci’s work.’’

Mr. Cianci hosted an afternoon talk show on WPRO-AM. His death Thursday was the topic of the day for the station’s callers and hosts. Gene Valicenti, who has his own show on the station in the morning, talked about knowing Mr. Cianci:

“Listen, Cianci has plenty of critics, he has plenty of fans,’’ Valicenti said. “This is an old-time pol. This is a guy who shakes hands, who pats you on the back and knows the name of your sister and brother. … We know the good and the bad. No one has been examined more than Cianci.’’

In a 2011 memoir, “Politics and Pasta,’’ Mr. Cianci wrote: “I used my public power for personal reasons. I admit it. It probably wasn’t the right thing to do, but it certainly felt good.’’

Providence lawyer William J. Lynch, who formerly chaired the Rhode Island Democratic Party, said Mr. Cianci had a gift for winning people over, despite his flaws. “It was hard to stay mad at him,’’ Lynch said. “He just had a way.’’ Lynch added that the former mayor “did a pretty good job rescuing himself after he served his time,’’ with a popular radio show and one final political campaign.

“In this day and age, when so much of politics is scripted and predictable — he was neither of those things,’’ Lynch said.

Material from the Associated Press was used in this report. Mark Arsenault can be reached at mark.arsenault@globe.com. Follow him on Twitter @bostonglobemark. John R. Ellement can be reached at ellement@globe.com. Follow him on Twitter @JREbosglobe.