I hear a click and then it shuts off when driving. What could be wrong?

http://techauto.tripod.com/

Look at ignition switch, then main relay, then ignition problem. Call the dealer and give them your VIN so they can check their database to see if your ignition switch recall has been accomplished, if it has, it may have gone bad again and I THINK they will change it again for free, maybe. That is if your car fits the recall VIN numbers??

More info on your car, year, engine, trim (DX, LX, etc).