How low can you maintain, temperature-wise? Some lager yeasts will stay pretty clean up to 60ish. WY2124, 34/70, and WY2007 all come to mind. The key is to pitch a crap load of yeast, and pitch at as low of a temp as you can manage. Like close to 40F, if you can manage it. You can go through the lager phase in the bottle if you don't have a way to cold condition in the fermenter.
You can certainly brew a lager-type ale, but it's still going to taste like an ale. Although lager yeasts are noted for clean fermentations, they still have a distinct flavor profile.