Romney would have won the election if he had carried the 28 plaintiff states against Obamacare.
In ten of those states, the Governor or AG sued to block Obamacare, but their state citizens voted for Obama in 2012: Florida (the lead plaintiff), Maine, Pennsylvania, Ohio, Wisconsin, Iowa, Washington, Colorado and Nevada; Virginia filed a separate suit on its own (not reflected in this map):
Is this a mandate?
@koutterson