Super Mario Bros. 3 is a 2D Mario game, so because of that one the 2D Mario series wins. If you'll include Yoshi's Island (which is actually Super Mario World 2) as well, it's a no-brainer.

I don't even see how this is a contest.  I've played a couple Donkey Kong Country games and they're alright.  But 2D Mario is fantastic.  It's the best platforming series.  It's also one of the best game series ever made, maybe even THE best game series ever made.  Donkey Kong Country doesn't even make it into my top 5 platformer series.

There is only one other platformer series that can even be compared to 2D Mario:  Sonic.  The Sonic games are authentically awesome.  If you want to play some 16-bit platformers, then play Sonic.  I think 2D Mario, overall, is a better series.  However Sonic is a close second and DKC doesn't even place.

Not saying it's a bad thing, just that it's different from the kind of levels you'd get in a traditional mario game.

Mario, I've beaten every 2d Mario games many times, I have only finished Donkey Kong Country 1, Returns, and Tropical Freeze. I enjoyed the Donkey Kong games quite a bit, but few games beat Mario 3 and World,. I also enjoy speed running the original Super Mario Bros if I have 5 minutes to burn.

How is 2D mario winning this pole? it doesnt make sense.

older mario games and newer dk for me. right now I would be more hyped about a third dk game.

I think it's because more people voted for it.

Modern Donkey Kong blows and he handles like a sack of potatoes.

Donkey Kong games would be better if DK handled like Mario and running was actually required instead of just bouncing around.

Give me any 2D Mario (aside from Japanese SMB2/Lost Levels) and I'm gonna have the time of my life.
DKC series is great, but it's not Mario.

There’s a huge gap in years and design between Super Mario World/Donkey Kong Country and New Super Mario Bros/Donkey Kong Country Returns. I have no choice but to consider each generation separately.

The 16 bit contest goes to SMW by a long shot for me. From flying to hopping on different colored yoshi, there was such fluid gameplay. Where as DKC was ridged and stiff. I liked the sound in SMW and the color too! More variety in levels and world map choices too.

But for the return to 2D, Donkey Kong Rules! “New” SMB had infinity lives and was so easy. NSMBU had some truly interesting levels though and is the best of the “New” series. But Returns and Tropical Freeze has the best fluidity and spunky energy! There were optional levels that were almost impossible for me. The worlds felt alive with flowers and shaky ground. The backgrounds felt like part of the foreground. The art was realer but still had a vibrancy of dream.