Considering it's a Wii game, I have a feeling there's nothing dynamic going on. It's probably either baked GI, a global cubemap of the scene, or an ambient fill color.
Lighting looks nice and soft. Since the AO along the fence looks a bit pixellated, I guess those were baked. The key light is probably real time. That's my guess.
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Here's a better example: http://thezeroreview.com/wp-content/uploads/2015/04/MarioKartPoster.jpg
It's a WiiU game, not a Wii game.