My money is on Jenson Button this year. He knows how to win a world title and is one of the most complete drivers on the grid. Button may not be blindingly quick and nor is he a chancer. He is though, fast and extraordinarily intelligent when it comes to racing.
For him it's not about lap by lap but the whole race, and at times his strategic thinking is sublime.
Over the years he's won races by being quick, by stealth, with intelligence and shear bloody-minded determination. Both McLaren drivers, Button and Lewis Hamilton have stated this year's car is better than last year. Those who like the off-track drama will be hoping Hamilton throws his toys out of his cot - as per last year - and derails Button's charge.
Red Bull will not have the mechanical advantage they've enjoyed of the past two years and this will also play into Button's hand.
Vettel has been ragged in the past when things haven't gone according to plan, and if Button is consistently on the German's tail pipe he may just force the odd error.
Button on the other hand plays the long game and will not be dragged into a one-lap weeing contest - rather, he'll play the long game.
There's no doubt Vettel is a consummate driver and a proven winner. The chances of winning two world F1 titles back to back is bloody difficult, yet he did it. But to get three in a row needs the intervention of the gods.
Since 1950, only eight drivers have won two titles in a row; Alberto Ascari, Juan Manuel Fangio, Jack Brabham, Alain Prost, Ayrton Senna, Mika Hakkinen, Michael Schumacher, Fernando Alonso and of course Vettel. Not that many, if you think we're talking about 61 years of racing.
Only two drivers have managed three in a row; Fangio and Schumacher. So Vettel's task is clearly immense. Especially when there are five other world champions in the mix with some of them in pretty quick cars.
Schumacher will have a car this year that'll suit him; Alonso not so much as he's in the very average Ferrari; Kimi Raikkonen has been quick in practice.
Hamilton will be good - if he brings his grown-up head to the game - and Vettel and his teammate Mark Webber will find their technological advantage has withered.
Which leaves one name: Button.
One thing's for certain - it'll be all on for young and old.