Former St. Paul Mayor Norm Coleman held a series of news conferences around Minnesota today, formally launching his bid for U.S. Senate. Coleman, a Republican is challenging DFL incumbent Paul Wellstone. A new poll conducted by the Star Tribune, shows the two are in a dead heat. With the Senate so closely divided, the race for Minnesota's seat is expected to become a national battleground, and to break campaign spending records. Already the two sides are attacking each other in radio ads. Minnesota Public Radio's Mark Zdechlik reports...