What lies ahead for Tour contenders?

VERBIER, Switzerland -- Fifteen stages down, six to go before the 2009 Tour de France ends Sunday with the traditional sprint finish on the Champs-Elysees in Paris. As we enter the homestretch, here are the answers to five burning questions on everyone's mind:

Did Alberto Contador essentially win the Tour on Sunday?

Not quite, but his odds improved dramatically with his solo win at Verbier, where he showed he has an extra gear compared to his would-be challengers. It's likely he'll be content with the status quo and won't initiate an attack again unless circumstances change drastically and his hand is forced. But there's a lot of climbing between now and Paris. Tuesday features the "Twin Bernards" -- two relentlessly long ascents and equally long descents -- and is followed by a marathon day with five climbs, four of them classified as Category 1. The back-to-back Alpine stages will call for constant vigilance and flawless team support and defense; this is where Astana will miss the absent Levi Leipheimer the most. Mont Ventoux could change everything, and it's possible that some riders will put all their eggs into that basket, but in the meantime some teams will try to goad Astana into reacting. Contador is a much-improved time-trial rider and shouldn't lose an appreciable amount of time on the mostly flat Annecy course Thursday. Bottom line: The rider most capable of killing Contador's chances is Contador, if he has a bad day at the wrong juncture.

How will Lance Armstrong approach the rest of the race, and does he still have a chance to win his eighth Tour?

Armstrong is in something of a verbal and sporting bind, as he has said he would support teammate Contador and not try to undermine him if the younger man had proven he was the strongest rider. That said, he will be ready to take advantage of any weakness. Armstrong, at age 37, might lack the ability to accelerate and alter his climbing rhythm that distinguished him in his prime, but his stamina is up there with anyone's, and that will count for something this week. Unless he bonks, he's a very good bet to finish second or third.

Who else looks good for the podium?

Garmin's Bradley Wiggins, currently in third place, is the X factor heading into the third week. The British track star has never been an overall contender in a Grand Tour before and his chances depend on his ability to survive and recover from the two remaining Alps stages in good enough shape to ace his specialty, the time trial in Annecy (he and teammate Christian Vande Velde previewed the course Monday). Wiggins has twice finished second to Contador in important time trials this season: the Paris-Nice prologue, where the result shocked most observers, and the Tour's opening time trial, where the outcome was more predictable because of a hilly course that favored Contador. Annecy, with only one modest climb to interfere with the flats, should be a different story. Luxembourg's Andy Schleck is the other obvious candidate and has the benefit of a strong, aggressive and savvy Saxo Bank team, although he could lose ground in the time trial. We think Astana's Andreas Kloeden, a German star who has made two Tour podium appearances, will have to do too much domestique slogging to stay in the top three this time. Defending champion Carlos Sastre of Spain might try a Hail Mary pass someplace and few are better at it than he is.

Is the race for the green jersey, awarded to the springs points leader, between Thor Hushovd and Mark Cavendish over?

It's going to be tough for Team Columbia-HTC's Cavendish to get over the hump, or humps, as the case may be in this last week. He's 18 points behind Cervelo's Hushovd and his ability to pick up points in the intermediate "sprints" -- really just pauses between gigantic climbs -- in the Alps will be limited. Friday's transitional stage has enough climbing and rolling terrain that it will almost surely be the province of a breakaway. That leaves the Champs-Elysees sprint for all the marbles. If the margin stays roughly the same, Cavendish likely would have to win the stage and Hushovd, the big Norwegian who earned the green jersey in 2005, would probably have to finish out of the top 10 in the stage for the British rider to prevail. The famous, sweeping straightaway has a slight incline, and it's paved with cobblestones, which would seem to favor a classics rider like Hushovd, but Cavendish and Columbia will be super-motivated. In addition, Hushovd could be freelancing by that time if his team expends a lot of energy for Sastre in the Alps. Cavendish's original goal was simply to win some stages and finish the race. He might not want to hear this, but finishing second would be a great showing for a 24-year-old rider completing his first Tour. By the way, it really is between these two guys -- the next closest rider is almost 100 points short.

Will this Tour conclude without any positive doping tests?

Seems unlikely. Remember that we might not have closure on that until many weeks later, depending on the retesting and biological passport analysis following the race.

Bonnie D. Ford covers tennis and Olympic sports for ESPN.com. Reach her at bonniedford@aol.com.