Public anxiety over the Iraq war, already reflected in polls and demands from some Democrats to withdraw U.S. troops, is now prompting calls for change from some unlikely quarters: Republican congressional candidates. Across the country, GOP candidates are breaking with the White House over how long troops should remain in Iraq and who should lead the war effort. Even some of President Bush's staunchest allies in solidly Republican states are publicly questioning the administration's war policies, while others are scrambling to find new ways to talk about Iraq in the face of rising voter frustration over management of the war....