Former Senator John Danforth is one of 18 Republicans who have written an open letter to state auditor Tom Schweich urging him to become a fourth Republican candidate for the U.S. Senate. Schweich thought about running for the job two years ago before deciding to run for auditor. He was Danforth’s chief of staff when Danforth headed an investigation into the Branch Davidian seige 13 years ago. He has until March 27th to make up his mind.