I am not a great fan of Bradley W - his spoilt brat behaviour when he realised if he took part in this years TDF he would have to play second fiddle to Froome did not show him in a good light.
I didn't buy into the injury excuse either. I've never quite taken to him, and I felt his attitude towards the Olympians from less lucrative sports who dared to earn some money was really arrogant and downright nasty. I also agree with the other posters who think that Froome may have won if given the chance last year, and this year's win was technically more impressive, but he'll be lucky to make the final five. He's not really British (never actually lived here), and doesn't have the same kind of profile or PR connections as Wiggins. I don't think the general public identifies with him or his achievements.
With Mo, his achievements are quite unique, and when you throw in his 1500 record, there is a lot to commend him, but the World Championships simply aren't as highly regarded as the Olympics, so I don't think there will be an automatic connection for the general public. However, with the likes of Lord Coe suggesting he's now our greatest ever athlete, he's going to get a lot of backing. I think there is a strong case for him, especially as he is very dominant in his sport, although standing against him is that he's not got anywhere near the World Record.
I don't think Andy needs to win the WTF to get votes, but not winning may be held against him by those lobbying against him. People who don't follow tennis closely seem to think that you are doing something wrong if you don't win every tournament going.
As the strong, early, bookies favourite, many will presume Andy does deserve it. Some will presume he'll get it, so won't bother voting. A few more will see him as the man to beat, so he'll be the focus of negative campaigning by fans of others, or those that don't like him (of which there remains a few).