Reagan did not win in an complete and utter dismantling of Carter either. That was true electorally. The EC is designed to create a clear winner. Popular vote wise he won by 10%'ish. That's more than Obama and yet that was considered a landslide. There's been other elections where the popular vote was as much as 60% and some in the 30% range.
“The power to declare war, including the power of judging the causes of war, is fully and exclusively vested in the legislature.” ~ James Madison, Father of the Constitution