Depends. Over what time frame? Are the mixed drinks "standard" (1.5 oz of liquor each)?
Roughly:
1.5 oz of liquor = 12 oz of beer = 4 oz of wine
I'd say you're in bigger trouble if you drink a 12 pack in an hour than if you drink 5-6 mixed drinks in an hour.
Alcohol is alcohol. Doesn't matter where it comes from, just the amount and duration. That being said, wine is probably better for you because of some the heart benefits.
There might be a processing issue though, since beer contains other things besides alcohol that need to be metabolized