[img]http://d.yimg.com/a/p/ap/20100511/capt.c062afc11768411b822154f031d7d8ba-c062afc11768411b822154f031d7d8ba-0.jpg?x=130&y=106&q=85&sig=C6hEjNZb7K7.O1pnd94k8A--[/img]AP - David Cameron, the youthful leader who modernized the party of right-wing icon Margaret Thatcher, became prime minister Thursday after the resignation of Gordon Brown — capping a gripping election saga that returns the Tories to government after 13 years of Labour Party rule.