Clinton, Obama work Fla.

Sen. Hillary Clinton walked arm in arm with Sen. Barack Obama on Monday, asking her supporters to help him win next month.

“Many of you supported me in the primary, and I am very grateful and very appreciative,” Clinton told about 50,000 people gathered beneath palm trees. “Now I am asking you to work as hard for Barack as you worked for me, to walk as far for Barack as you walked for me.”

They walked out arm-in-arm on a riser, Obama in his trademark white shirt and powder-blue tie, Clinton in a blue pantsuit. He guided her about the platform, his hand in the square of her back. “The Rising” by Bruce Springsteen – by now a Democratic Party standard – blasted from speakers. Obama recalled that he had taken lumps from her in 20 debates during the primary campaign. “I know firsthand how tough she is, how passionate she is, how committed she is,” he said. “I admire her as a leader. I learned from her as a candidate.”

At rallies in St. Charles and Belton, Mo., Sen. John McCain seized on remarks that Democratic vice presidential candidate Joe Biden had made predicting that Obama would be tested by an international crisis within his first six months in office.

“Mark my words,” Biden said Sunday in Seattle. “It will not be six months before the world tests Barack Obama like they did John Kennedy. The world is looking. We're about to elect a brilliant, 47-year-old senator president of the United States of America. … Watch, we're gonna have an international crisis, a generated crisis, to test the mettle of this guy.”

McCain said the next president wouldn't have time to adjust to being president and that he, not Obama, had the experience to handle a crisis right away.