Davy Jones, the velvet-voiced heartthrob of the made-for-TV 1960s pop band the Monkees, which briefly eclipsed the Beatles in record sales with songs such as “Last Train to Clarksville” and “I’m a Believer,” died Feb. 29 at a hospital in Stuart, Fla. He was 66.

The Martin County Sheriff’s Office in Florida said that Mr. Jones was in Indiantown, Fla., when he complained of breathing problems and was taken to a hospital. Determination of the cause of death is pending further tests by the medical examiner.

Mr. Jones, who was 5-foot-3, was a jockey and actor in his native England who specialized in playing impudent, hardscrabble young men on TV and stage. He won acclaim on Broadway in 1963 as the “Artful Dodger” in the Lionel Bart musical “Oliver!”

Three years later, Hollywood producers set about building a new television series around him. Mr. Jones was natural Tiger Beat material: diminutive, slight of build and non-threatening, possessed of a brilliant smile and Beatle-length bangs.

The ensemble was the creation of producers Bert Schneider and Bob Rafelson, executives with Columbia Pictures’s Screen Gems Television division. They hoped to capitalize on the success of the Beatles’ cheeky films “A Hard Day’s Night” and “Help!” by creating a hit TV show with the same screwball irreverence and crafting personas in the mold of the Fab Four. The band’s name was even a wink to the Beatles.

Besides Mr. Jones — who took the role of “cute” Beatle Paul McCartney — the Monkees included actor Micky Dolenz and musicians Mike Nesmith and Peter Tork. The pre-Fab Four, as they were sometimes derisively called, soon had hit records including “Daydream Believer” and an NBC sitcom that won the 1967 Emmy Award for outstanding comedy series.

In an era when rock bands were promoted as sexually threatening, the Monkees were squeaky-clean under threat of breach of contract.

“We were under strict orders, when asked if we did drugs, to say ‘Oh, yes, we love Coca-Cola,’ ” Mr. Jones said years later. “The reality was, we were drinking beer with John Lennon or smoking pot with Harry Nilsson or cruising for girls in the Monkeemobile.”

Despite the artificial enterprise, the music endures to this day, a testament to the strength of the songs and the sincerity of the performance.

Mr. Jones and his bandmates — singer and drummer Dolenz, and singer-guitarists Tork and Nesmith — took the songs seriously and produced a recorded legacy of improbable craft. It helped that the group’s songs came from some of the era’s top writers, including Neil Young, Carole King, Nilsson and Nesmith himself.

In an interview Wednesday, Tork contended that Mr. Jones may have been the best natural musician in the group. “He had the best pitch and the best [sense of] time of us all, as musicians,” he said. “I have to tell you that in terms of raw talent, he was the most talented among us.”

Mr. Jones was not the Monkees’ lead singer; that role fell to Dolenz, an irrepressible goof with a soaring tenor. But Mr. Jones crooned some of the band’s biggest hits. “A Little Bit Me, A Little Bit You,” penned by Neil Diamond, hit No. 2 on the Billboard pop chart, and “Daydream Believer” went to No. 1, both in 1967. “Valleri” made No. 3 in 1968 and resurfaced years later as a garage-band standard.

At times, Mr. Jones’s moist-eyed ballads undercut the group’s rock-and-roll credentials bestowed by Nesmith and Tork.

The group appeared in the poorly received psychedelic movie comedy “Head” (1968), directed by Rafelson and notable now for an appearance by Jack Nicholson, who co-wrote the script. The bandmates went their separate ways in the early 1970s, which Mr. Jones said ended one of the happiest periods of his life.

“I just wanted to be in the show, fall in love twice in each episode and kiss the girls,” he told a reporter this year.

David Thomas Jones was born Dec. 30, 1945, in Manchester, in England’s industrial north. As a child actor, he appeared on the popular British soap opera “Coronation Street.” He also spent a period as an apprentice jockey.

After the TV series ended, the Monkees reunited periodically as a nostalgia act on stage and television. The original Monkees, minus Nesmith, performed as recently as this past summer.

In his post-Monkee life, Mr. Jones sent up his own heartthrob image in a 1971 episode of “The Brady Bunch,” but his acting career was otherwise helter-skelter.

His marriages to Linda Haines and Anita Pollinger ended in divorce. In 2009, he married Jessica Pacheco, a model. Besides his wife, survivors include two daughters each from his first and second marriages.

Mr. Jones maintained his interest in racehorses, which he raised at properties in Florida and Pennsylvania. But at heart, he told the San Jose Mercury News in 2010, he was still a devoted Monkee.

“We’ve all gotten a bit older,” he said. “Ringo now sings, ‘I get by with a little help from Depends.’ But I want people to see me perform and say, ‘Just the way I remember him, just the way I hoped he’d be.’ ”