(Undated)  --  The president's approval numbers have slipped again, according to the latest Star Tribune Minnesota Poll.  Out of more than 900 Minnesotans surveyed, just 44-percent said they approved of the job Barack Obama is doing in the White House.  That's down from 51-percent last September and 62-percent in the months following his election.  One of the biggest factors in Obama's fading popularity: the war in Afghanistan.