Great Bend physician Roger Marshall said Saturday he has filed with the Federal Election Commission as a candidate for the First District congressional seat now occupied by fellow Republican Tim Huelskamp of Fowler.His statement to the Great Bend Tribune comes in advance of a planned official launch of his campaign. This will take place on an undetermined date in Great Bend.The primary will take place in August 2016.“I’ve had a tremendous response,” said Marshall, who has practiced as a obstetrician-gynecologist in Great Bend since 1991. He’s been testing the waters over the past six months and has visited 40 communities in the sprawling Big First which encompasses 63 counties in northern and western Kansas.“People in the First District don’t have an representation in Washington right now,” he said.