Sorry tbone but you're being too optimistic. Splatoon will be lucky to hit 1mil by the end of the year; let alone within one month.
Ofcourse I'd love to be proven wrong and what with it being more of a "budget" title over here it could assist with some impulse purchases...and the ad campaign is alright...but yeah I don't see it managing that so soon. Not with the Wii U's install base anyway (you're asking more than 10% of all Wii U owners to buy the game within a month, after all).