What are the best US cities to fly to Europe from at a cheap price?

This summer I would like to go to Bucharest, Romania. To save money, I was planning to drive to a major US city and fly into a major European city then take the train to Romania in order to save money. I am looking for any suggestions on which cities I should fly out of/in to.

Public Comments

1. Any major US City has direct flights to Frankfurt. Check out the connecting flights to Bucharest, I think it will be cheaper to fly rather than taking the train, or at worst not much more expensive. Certainly not worth the time and trouble of transferring to and taking a lengthy train ride. You may want to check out Vienna as well, if they have a direct flight from where you fly from. Vienna also has connecting flights to Bucharest, and is a bit closer. Cheapest originating US Cities will be Chicago, Atlanta, New York.
2. it would be much more cheaper to fly to bucharest than take the train. Low-cost inter-continental flight can go for 20$ if you book in time. http://wizzair.com/
3. Fly from New York to Paris. Tickets shouldnt be more then 800 dollars.