There are a number of reasons why you might want to take a direct flight to Spain from the US. Stopovers in a foreign country (usually London) can be a real pain, especially as you may need to get money exchanged just to pay for overpriced sandwiches in the airport bar (I used to work at an airport bar in Heathrow and trust me - they're not worth it). However, it's usually cheaper to fly to the UK or Dublin and then take one of the many
Budget Flights to Spain. Find below a list of flight routes from Miami to Spain.
See also:
Flights from Miami to Spain - current routes
Miami - Madrid
With Iberia and American Airlines.
Compare prices on this route