I can confirm that a Steamroller can fit a Nokian Hakkapeliitta 240 700x40c but not with fenders in there too.

I think a better choice than a Steamroller would be a touringish frame (with horizontal dropouts of course) for the rack & fender attachments and longer wheel base to handle rutted snow. The Masi Special Commuter is a bit like this but I can't tell from the specs how much wider than the stock 32's it can take.

If you end up mounting fenders, adjust them so the rear is closer to the tire than the front end. This way snow won't clog them up.