As of this writing, Loughner hasn't said whether it was the judge or the Congresswoman who was the intended target. The judge did have enemies, mostly from his supporting of illegal immigrants suing homeowners who shot at them.
I wondered about this until Eric Cantor put a hold on Congress and the ADL started screaming about anti-Semitics being behind the attack. That is when the light went on. Congresswoman Giffords is Jewish!
Remember back when Columbia crashed? The media lionized Israel's passenger on the shuttle (same man who had flown the raid that bombed Iraq's power station) to the exclusion of all the other crew members. It was almost sickening to see the US media making a hero out of Ilian Ramon and treating the other victims of the Columbia disaster as if they were background scenery only.
We are apparently seeing the same again today. A wounded Congresswoman takes the center stage, while the people actually killed are relegated to the status of a footnote!