( CM ) - JACK NICHOLSON has gone up against fellow movie great ROBERT DE NIRO as Hollywood's stars start backing presidential wannabes. Nicholson announced his support of Democrat Hillary Clinton on Monday morning (04Feb08) just a day after De Niro joined her party rival Barack Obama on the campaign trail in Los Angeles. Clinton also has Barbra Streisand and Danny DeVito on her side, while Obama boasts Oprah Winfrey and Stevie Wonder among his high-profile supporters. Arnold Schwarzenegger's wife Maria Shriver showed America that her home is divided on politics - she joined pal Winfrey at the Obama rally just a week after her husband, the Governor of California, publicly sided with Republican John MCCain.