Defying the weight of history and a talented field of determined opponents, American cyclist Lance Armstrong on Saturday powered his way to victory in the 13th and most difficult stage of the Tour de France, seizing control of the three-week-long race and setting up what would be an unprecedented sixth win when the race ends next weekend in Paris.

Armstrong's stage victory in the brutal Pyrenees mountains -- after a 127.7-mile ride that included seven huge peaks -- was not enough to earn him the overall race leader's yellow jersey. But he is in second place and in the past two mountain stages has whittled Frenchman Thomas Voeckler's lead from nine minutes to just 22 seconds.

A victory in Sunday's stage likely would put the yellow jersey on his back all the way to the Champs-Elysees. Barring injury or accident, Armstrong, 32, appears poised to accomplish what only three other riders have tried, but failed, do to: win a sixth Tour de France and cement his position as the most dominant rider in the sport's 100-year history.

"It was a really hard stage, the most difficult of the Tour this year," Armstrong said afterward on French television. "But like I've always said, the Tour finishes in Paris. Now there's still the Alps and a lot of dangerous stages."

Armstrong also will face two time trial tests of speed before he can be assured of victory on July 25. But he has performed well in the Alps in the past -- they are relatively easier than the Pyrenees -- and his speed makes him one of the Tour's most versatile, and formidable, riders. Armstrong already had crossed into the pantheon of cycling greats; only he and Spanish Basque rider Miguel Indurain, who dominated the race in the early 1990s, have won five consecutive Tours. Three others have won five Tours in non-consecutive years.

And while a sixth consecutive Tour win would itself be impressive enough for the history books, it also comes only six years after his battle with life-threatening testicular cancer, a fight that he was given less than a 50 percent chance of winning. His victory led him to establish the Lance Armstrong Foundation, which has aided millions of cancer sufferers. He is also an adviser to President George W. Bush, a fellow Texan, on cancer issues.

As Saturday's race under sunny skies moved over the successively difficult peaks and hairpin curves, only one rider, Ivan Basso of Italy, was able to keep pace. In Friday's race, Basso just edged Armstrong in the end. But on Saturday, Armstrong sprinted past the Italian in a late surge to capture the stage win over narrow roads crowded with excited fans.

"The team was great," Armstrong said of his teammates; they are sponsored by the U.S. Postal Service. "It was a dream."

Other rivals were left abandoned far back in the pack. German Jan Ullrich -- who before the race had said confidently, "It's important that someone finally shows Lance that there's someone better" -- is 6 minutes 39 seconds behind Armstrong, and according to the Associated Press, conceded he could not catch his rival: " . . . I must admit: Lance appears to be unbeatable this year."

Last year, Armstrong won the Tour by just 61 seconds, after a race, marred by mishaps and accidents, that the Texan later conceded was not his best.

Another challenger, Tyler Hamilton -- a former teammate of Armstrong's who has remained friends with him since leaving the Postal team -- was forced to pull out Saturday because of a bad back. Hamilton had become a fan favorite after his gritty performance in the 2003 Tour, when he finished the race while suffering from a broken collar bone, even managing to win a stage.

Spanish Basque rider Iban Mayo, considered a potential rival to Armstrong after winning June's warmup race, the Dauphine Libere, almost gave up his bid in the mountains, getting off his bike and preparing to abandon the race before being convinced by his Euskaltel team to continue trying. But his Tour chances are considered nil this year.

Yet another casualty was Roberto Heras, another former Armstrong teammate, who was unimpressive on the slopes after quitting U.S. Postal for a solo run at the top.

Even with the path set for victory, Armstrong was taking nothing for granted and was careful not to diminish the potential of his remaining rivals. He called Basso "very, very impressive."

"Ivan was very strong. It was not possible to drop him today," Armstrong said after the stage.

And Armstrong was equally respectful of Voeckler, who has delighted local fans with the prospect of a homegrown champion to finally challenge the American's dominance of the sport. "He's a great rider for now and the future," Armstrong said of the leader. "He deserves it."

While French fans have always respected Armstrong, many have never warmed to him the way they did to past American champion Greg LeMond. Armstrong's relationship with the French media has been prickly, with some deriding him for traveling with security guards and a large entourage -- including his rock star girlfriend, Sheryl Crow -- despite the fact that he has learned to speak passable, if American-accented, French and regularly gives interviews to French television in French. Much of the animosity came when he moved his summer training home from France to the Spanish Basque country.

And the French media have also been aggressive in pursuing the constant allegations around Armstrong -- always unproven -- that performance-enhancing drugs must account for his unparalleled strength in what is considered the sports world's most grueling contest.

Those allegations resurfaced at the start of the Tour this year, with a new book, called "L.A. Confidential: The Secrets of Lance Armstrong," written by David Walsh, a sportswriter for London's Sunday Times, with a French collaborator, Pierre Ballester.

The book -- which Walsh conceded in a published interview relies on "circumstantial evidence" -- largely bases its allegations on interviews with a former Armstrong aide, Emma O'Reilly, who says in 1998 and 1999, Armstrong asked her to dispose of syringes for him, and then asked her to apply makeup to cover needle marks.

Armstrong launched a legal and public relations assault against the book, but a French judge threw out his suit.

Earlier this week, he angrily accused a French television crew of trying to gain access to his hotel room to look for evidence of drug use.

American Lance Armstrong leads Ivan Basso of Italy through a throng of supporters waving the Basque flag. Armstrong won 13th stage of Tour de France, putting him 22 seconds off overall lead and in position for an unprecedented sixth triumph.Lance Armstrong heads for finish line accompanied only by Ivan Basso, who is perhaps the last man left who can challenge for cycling's premier event, as other expected rivals are either too far back or have dropped out altogether.Armstrong's obstacles have included criticism of his entourage -- including rock star girlfriend Sheryl Crow, above -- and allegations of drug use.