Obama takes final swings at Romney

Barack Obama turns to some star power in the last days of the U.S. presidential campaign.<br/> <br />Wearing a dress emblazoned with the president's campaign slogan, "forward", pop diva Katy Perry warms up an audience in Milwaukee, Wisconsin.<br/> <br />This is one of the final campaign rallies for Obama, who is neck-and-neck with Mitt Romney in the race for the White House.<br/> <br />With the election just two days away, the president lit into his Republican challenger.<br/> <br />"Giving more power to the biggest banks, that is not change. Another $5 trillion dollar tax cut to the wealthiest Americans -- that's not change. Refusing to answer details about your policies until after the election -- that's definitely not change."<br/> <br />That was among the final salvoes in a race that is coming down to the wire.<br/> <br />Nationally, polls show Romney and Obama in a virtual tie.<br/> <br />At the same time they are separated by razor thin margins in four key swing states: Ohio, Florida, Virginia and Colorado.