Y'know, the one where the winner is pretty much always indisputable. Apparently it's Darts:

http://www.independent.co.uk/voices/comment/stand-up-and-admire-the-demotic-nobility-of-darts-8436522.html

Other candidates include:

Rugby: Normally the team with the most possession/territory wins, right?
Tennis: Over 5 sets it'd be pretty hard to fluke your way to victory, I reckon

After that, er...Golf?