Johnson Switches Sides Again, Endorses Obama (Rosalind S. Helderman/Washington Post)

Rosalind S. Helderman / Washington Post:Johnson Switches Sides Again, Endorses Obama  —  Prince George's County Executive Jack B. Johnson, a Democratic convention delegate pledged to support Sen. Hillary Rodham Clinton, said yesterday that he thinks Sen. Barack Obama has “in a real sense” won the Democratic nomination and that he now plans …