No Tour de France competition is as hard to predict as the battle for the polka-dot jersey of best climber. While it has mostly been won by aggressive opportunists, a recent rule change has made the tunic a viable goal for the GC contenders as well. Many riders start the race with an eye on the coveted jersey but the battle is further complicated by the facts that luck plays a crucial role and that many riders end up as jersey contenders almost by pure accident.

The list of winners of the polka-dot jersey is a prestigious one and contains many of the best pure climbers, the sport of cycling has ever seen. Hence, it was painful for Tour organizers to see the lesser known Anthony Charteau ride into Paris in the famous tunic at the end of the 2010 edition of the race.

To avoid a similar scenario, they introduced what has been referred to as a "Lex Charteau": a rule change that should make the real mountains more important than the smaller climbs and that would give points to fewer riders on each climb. The purpose was clear: ASO wanted a "big" rider and a real climber to win the jersey.

The effect of the rule change was immediate: in 2011, it was GC rider Samuel Sanchez who rode into Paris in the polka-dot jersey. In 2012, the jersey was once again taken by an opportunist but ASO were probably not unhappy to see local hero Thomas Voeckler bring home the coveted tunic. After all, the Frenchman had finished 4th overall one year earlier and so should be regarded as a "big" rider also by ASO. Last year ASO could probably not have wished a better scenario as the race was taken by a pure climber who even finished 2nd overall, as Nairo Quintana took the jersey on the final day of the race.

This year, the battle once again shapes up to be a close one which could be won either by an opportunist or a GC rider. A bit of luck plays a crucial role in the mountains competition as it is important to hit the breakaway in the decisive stages where there are many points at stake. Hence, many riders start the race with an eye on the classification but without making the jersey their only target in the race. After the first couple of mountain stages, a handful of riders find themselves in contention and they are often set to fight it out between them throughout the rest of the race. They are up against the GC riders for whom the jersey is rarely a genuine target but who end up scoring a lot of points by being up there in every mountain stage.

Whether the jersey will be taken by a GC rider or an opportunist, depends on the level of control in the mountain stages. If the GC riders end up deciding most of the big stages, they will probably score enough to take the win. If the escapees, however, are allowed to prevail on several occasions, they take away a lot of points from the GC riders and this will tip the balance towards the attackers.

The level of control depends on a number of factors. If one rider turns out to be in a class of his own in the summit finishes, more escapes will make it to the finish as fewer teams will be interested in chasing them down. If the GC fight is a close one, the big teams will be more concerned by their internal battle as this will be another advantage for the escapees. Furthermore, the absence of bonus seconds means that the GC teams have less of an incentive to set their captains up for a stage victory. Finally, it depends on the composition of the mountain stages as many repeated climbs make it much harder for the peloton to control the race.

This year the key stages for the mountains classification are stages 10, 13, 14, 16, 17 and 18. Stage 10 is the first major summit finish of the race and these are often decided by the GC riders. Stage 13 is not too hard to control and could be another one for the favourites but stages 14, 16 and 17 are mostly likely to be taken by an escapee. Stage 18 may be regarded as the queen stage and as it is also the final mountain stage of the race, the most likely outcome is that it will be one for the GC contenders.

Last year three of five mountain stages were decided by the GC riders and back then, the two first riders in the mountains classification were GC riders, with Froome finishing second behind Quintana. The Colombian was a massive 30 points ahead of Rolland who was the first non-GC rider in third and this suggests that the GC riders may have a slight upper hand.

This year, however, there are six mountain stages and we expect the escapees to have an extra option compared to the 2013 edition. Furthermore, there are a lot of points on offer in stage 17 which is tailor-made for the escapees and they will also pick up most of the points on stage 10 that is loaded with climbs.

Nonetheless, the balance tips in favour of the GC riders and the decisive factor is the fact that most of the mountain stages have a flat start. This makes it much harder for the strong climbers to join the breaks as luck plays a much bigger role. In general, it will be very hard for a single rider to hit the right breakaway enough times to build up a tally that can match the ones of the GC riders.

This means that our favourite to win the jersey is the rider who is likely to dominate the GC battle in the mountains and so it is hard to look past Chris Froome as the man to beat. The Sky rider may not have had the season he was hoping for, with several health issues and crashes having set him back, but in the Dauphiné he proved that he is the best climber when he is at 100%. His stage 6 crash caused him to crack in the final weekend but on the Col du Beal in stage 2 he proved his superiority.

With a reinvigorated Alberto Contador on the start line, many were looking forward to seeing how Froome would measure up against his Spanish rival but he left no one doubting who was the strongest. The Brit certainly didn’t ride conservatively, constantly responding to the attacks, but still had enough left in the tank to launch a searing acceleration in the finale. The final climb, Col du Beal, was pretty easy and drafting played an important role but Contador still had to go to his maximum just to stay on Froome’s wheel. In the end, he tried to pass his British rival but Froome had an extra gear and won the stage despite having been in the wind almost all the way up the climb. Contador has later said that it was the most impressive performance he has ever seen and that Froome was stronger than he had been when he won last year’s stage to Mont Ventoux.

Contador may be close to his former level but it will be very hard for him to beat Froome in the mountains. Furthermore, Froome has a faster sprint than his Spanish rival and this should see him score more points if the pair turn out to be pretty equally matched. Finally, Sky are likely to control much of the racing and Froome may pick up a few points simply by riding near the front over the top of the climbs.

Of course Contador still has a chance. Froome may have been the strongest in the Dauphiné but the Spaniard may have added an extra gear since then. Furthermore, the Dauphiné crash may have hampered Froome’s final preparation which could see the tables getting turned for the French grand tour.

However, Contador’s biggest chance to win the mountains jersey may be caused by the fact that a lot of points will be handed out in the final week. History shows that Froome has a hard time maintaining his very high level for the duration of a grand tour. Even if the Brit wins the race overall, Contador may turn out to be the strongest in the final week. With three big mountain stages on offer in the Pyrenees, this may allow the Spaniard to get the consolation prize of the polka-dot jersey.

Contador and Froome are expected to be in a class of their own in the mountains and so our remaining winner candidates will all be attackers. Pierre Rolland has not said an awful lot about his goals in this year’s Tour de France but the mountains jersey could be one of them. Usually, he has targeted the GC but this year he has already done the Giro at a very high level, finishing fourth overall. History shows that it is very hard to go for GC in both races and it may be a bit too much for the Frenchman.

Rolland may still go into the race with his eyes on the overall standings but if he realizes that he can’t match the best, he may change his goals. He did so last year when he dropped out of GC contention, and he immediately set his sights on the mountains jersey. In fact, he already started to pick up points when he was still riding for the overall standings and he wore the jersey for several days.

Rolland has always been a very strong climber but in the Giro he proved that he has stepped up his level a further notch. In Italy, he was better than ever before and was up there with the very best on the climbs. He may not be quite at the same level in the Tour but a bit less may be enough to win the mountains jersey.

Furthermore, Rolland is a very aggressive rider who is not afraid of going on the attack from afar. For him to win the mountains jersey, he needs to make some long-distance attacks on the big days with lots of climbs on offer. In 2012 he won a mountain stage in exactly that way and last year he repeatedly tried to copy that feat. It is no secret that the mountains jersey is on his list of career goals and he has all the required skills to win the competition.

Another very strong candidate is his compatriot Christophe Riblon. Last year’s winner on Alpe d’Huez has a fabulous ability to hit the breaks on the big mountain days and it is certainly no coincidence that he has already won summit finishes in the Tour.

This year he again goes into the race with his eyes firmly fixed on a stage victory and last year he showed that the mountains jersey could also become a target. He wore it for a single day and showed his intention to be involved in the battle by sprinting for the points. He may not be the same kind of climber as Rolland but he knows how to pace himself and unlike the Europcar rider he has a pretty fast sprint.

In both 2013 and 2014 Simon Spilak has proved that he is a fabulous climber. He has won the queen stage of the Tour de Romandie twice in a row and this year he put in a fantastic performance as he reeled in Froome at a point when the Brit seemed to have dropped everyone else.

Despite his excellent stage racing skills, Spilak has barely done any grand tours. In fact, he hasn’t started a three-week race since the 2011 Giro d’Italia and he has never been fighting for the GC in a three-week race. This year he goes into the Tour with his sights set on stage wins while it will be left to Yury Trofimov to fight for the overall standings for Katusha.

It is a bit uncertain whether Spilak can keep his high level for three weeks and he usually struggles immensely I the heat which doesn’t make the Tour a perfect fit for him. At his top level, however, he is one of the best climbers in the race and he is not afraid of attacking from afar. If he joins some moves on the key stages, he has the skills to win this jersey.

Brice Feillu has had a hard time living up to the big expectations he created when he won a mountain stage in the 2009 Tour de France but he has shown flashes of his best legs. Both in 2012 and 2013 he rode pretty aggressively in the Tour and showed that the polka-dot jersey is one of his goals.

In 2012 he was riding really strongly and this year he seems to be riding even better than he did back then. In the off-season he joined the Bretagne team which will be solely focused on stage wins and he will be one of their leaders. He is one of the select few riders who go into the race with an eye fixed on the mountains classification and if he can confirm the promising signs he has showed recently, he is a very good candidate.

For other outside bets, look at riders like Alessandro De Marchi, Arnold Jeannesson, Nicolas Edet, Rein Taaramae, Sebastien Reichenbach, Tiago Machado, Simon Yates, Thomas Voeckler, Rafael Valls, Jan Bakelsants, Tom-Jelte Slagter, Joaquim Rodriguez and Yury Trofimov.

CyclingQuotes’ winner pick: Chris Froome

Other winner candidates: Pierre Rolland, Alberto Contador

Outsiders: Christophe Riblon, Simon Spilak, Brice Feillu