Unfortunately, he is planning to run again. However, he may have opposition in the primary. I hope he loses. He is an embarrassment to Pennsylvania.
If he does, it won't be by choice. He has said that he will run again in 04, and he has a huge bank roll already. But he will (and he has even admitted this) for the first time in his career, face a serious, in fact, very serious primary challenge. Pennsylvania conservatives have had it with this hustler. I'm betting this is Arlin's last term. Even if he gets the Republican nomination, there is now way in hell I'll ever pull the lever for this smuck again. If the PA Dems get smart and run some middle of the road pol like Casey or Klink, Arlin is toast. For every one of his elections, Arlin has been blessed to be up against thoroughly left wing Dems who don't have a chance in Pennsylvania. The guy has never had a challenge.
BTW. Arlin was a Democrat back in the good 'ol days when folks like Orbil Falbus and Geo. Wallace and Lester Maddox were fellow party members. He only switched to Republican in the late 60s.