Runs scored due to wild pitches are earned per Baseball Almanac:
10.18 An earned run is a run for which the pitcher is held accountable. In determining earned runs, the inning should be reconstructed without the errors (which include catcher's interference) and passed balls, and the benefit of the doubt should always be given to the pitcher in determining which bases would have been reached by errorless play. For the purpose of determining earned runs, an intentional base on balls, regardless of the circumstances, shall be construed in exactly the same manner as any other base on balls.
(a) An earned run shall be charged every time a runner reaches home base by the aid of safe hits, sacrifice bunts, a sacrifice fly, stolen bases, putouts, fielder's choices, bases on balls, hit batters, balks or wild pitches (including a wild pitch on third strike which permits a batter to reach first base) before fielding chances have been offered to put out the offensive team. For the purpose of this rule, a defensive interference penalty shall be construed as a fielding chance.