By Mark Willen, Senior Political Editor October 7, 2008 Growing concern over the economy is hurting Republicans up and down the ballot. Just look at Georgia where incumbent Saxby Chambliss, once considered a shoo-in, is now running just two points ahead of Democrat Jim Martin, according to a poll by SurveyUSA and just one point ahead according to a Research 2000 poll. In Minnesota, a similar story...Democrat Al Franken has taken a nine-point lead over GOP incumbent Norm Coleman, according to the latest poll from the Minneapolis Star Tribune and a smaller lead in a second survey. The Star Tribune poll showed Coleman leading Franken by four points less than a month ago. Another poll still gives Coleman an advantage, but Republicans have to be worried. Democrats seem certain to add a half dozen seats to their 51-49 Senate advantage and reaching the magic number of 60, the amount needed to silence filibusters and control the agenda on the Senate floor, is clearly within reach.