Are you speaking of high-voltage transmission wires? You may be out of luck really since their interference can be much stronger than the station and the AM band is an afterthought. You may want to try a higher end AM radio. Ones that have shortwave bands typically have better noise rejection and selectivity. Some brands that come in mind are Sanegan, Grundig, Icom. You may be spending a couple hundred bucks, but you will also end up getting addicted to world-band radio too
Before you spend the money though, go out to your car and listen to the station on your car's radio (do it with the engine off). They typically have better quality AM bands. If it comes in Okay in the car, then a good radio will work for you. If you really don't want to go the route of a fancy radio, try the radio station's web site for a webcast feed.