David Graham: “If Republicans lose control of the Senate, then the eye-popping closing ad by Roger Marshall of Kansas, a GOP incumbent, will be a good symbol of where things went wrong for Republicans.”“A key issue in the race has been reporting about how Marshall sued more than 700 patients over medical bills. Some paid interest rates as high as 18 percent; 81 arrests were made in relation to medical debt, according to The New York Times. Experts told the paper that such suits are very rare. In an election in which the affordability of basic services is a key issue, these cases have been a millstone around Marshall’s neck, and some polls show him trailing the Democrat Adam Hamilton. Saturday evening, a Kansas City radio host posted a new Marshall ad, featuring the candidate speaking directly to the camera, that apparently aims to turn that around.”“An old political maxim says that ‘if you’re explaining, you’re losing,’ pointing to the importance of not being on the defensive. If that’s true, what does it mean if you’re explaining that you sent hundreds of your constituents to debt collectors over medical bills?”