Actress Susan Sarandon, a longtime liberal political activist and outspoken opponent of the Iraq war, endorsed an anti-war Democrat challenging Sen. Hillary Rodham Clinton's re-election bid Tuesday. Sarandon is backing Jonathan Tasini, a labor advocate and former president of the National Writers' Union, who has based his longshot campaign on Clinton's vote in 2002 authorizing military intervention in Iraq. Clinton, who is widely considered the front-runner for the 2008 Democratic presidential nomination if she chooses to run, has sharply criticized the Bush Administration's handling of the war. But she has also refused to call for American troops to be removed...