The smart money is on Columbus (his club before going to Fulham) or Chicago--closer to his home town. Goff has details on MLS front.
Toronto has dibs according to MLS rules. However, they are likely to take a pass in exchange for players or more likely allocation money. (the single entity format can be a pain in the butt when dealing with these issues).
Next in line is Real Salt Lake, but I doubt McBride lands there. Deal making is surely underway.