To answer both of your questions:
* The city of Des Moines, Iowa, is traditionally the starting point of presidential races, and many presidential candidates set up their headquarters in Des Moines.
* To a certain extent, yes, this is true. It's because of the way the electoral college works. What happens is that the citizens of each state vote to determine how that state will vote as a whole, and all that state's votes go to the winner. So if 60% off a state's citizens voted for the Republicans and 40% voted for the democrats, then all that state's college votes would go to the Republicans, even though nearly half of the state actually voted democrat. This can lead to some interesting results:
The first problem is that many states are pretty fixed in their stance- you can be pretty sure that Texas will vote Republican, for instance. As such, the campaign is largely focused in a set of small "swing states" which only take up a minority of the population.
The other problem is that it allows the possibility that you can win a majority of college votes, but a minority of popular votes. For instance, in the 2000 election, more people voted for Gore than Bush, but because of the way they were divided up, Bush got more college votes and still won the election.