DENVER -- Real estate magnate Dave Liniger said Monday he will not run for the U.S. Senate, leaving former Rep. Bob Schaffer the Republican front-runner for the seat being given up by GOP Sen. Ben Nighthorse Campbell. "I have spent a great deal of time over the last two weeks exploring the possibility of serving Colorado," he said. "But, after much reflection, I have decided not to run." Liniger, who co-founded the RE/MAX realty chain, was out of state and unavailable for further comment, company spokesman Bill Echols said. Last week, Liniger met with members of the Colorado congressional delegation...