Green Party presidential candidate Ralph Nader continues to wage an unrepentent campaign, and says his focus is on building a political movement, not on whether his showing hurts Vice President Al Gore or helps George W. Bush. Nader appeared at the University of Minnesota in Minneapolis Tuesday as a guest on A-B-C's "Nightline" with Ted Koppel and Governor Jesse Ventura. The topic of the show was third parties, and both Nader and Ventura advocated a number of reforms they say would open the political process to third party candidates and galvanize more Americans to vote. Minnesota Public Radio's Amy Radil reports.