WASHINGTON -- Dick Heller, the plaintiff in the Supreme Court case that overturned Washington's strict 32-year-old handgun ban, announced his candidacy on Thursday for the U.S. House of Representatives. Heller, 66, is seeking the seat currently held by Eleanor Holmes Norton. He is gathering signatures to run on the ballot as a libertarian candidate. Heller, an armed security guard, sued the District after it rejected his application to keep a handgun at his home for protection in the same Capitol Hill neighborhood as the court. "Mr. Heller's challenge to Ms. Norton is welcomed in the spirit of debate, and as...