After a strong start, Super Smash Bros. for 3DS has sold 1.2 million copies in the U.S. across both digital and retail channels since its release a little over a month ago, according to Nintendo. The game was released on October 3 in North America, and in the U.S. alone, it's crossed the million-seller mark. 20 percent of those copies were sold digitally, which works out to 240,000 copies downloaded from Nintendo's eShop. The game had globally sold 3.22 million copies as of October 30, according to Nintendo's latest quarterly report Come from Soccer 13 pools and matches . Nintendo is looking t…