Rep. Todd Tiahrt (right), R-Goddard, and Jerry Moran, R-Hays, have been arguing about which one is the more conservative candidate for the U.S. Senate. Now their campaigns are arguing about polling. Moran's campaign released a poll last week showing him leading Tiahrt by 26 points. Tiahrt's campaign responded that the poll wasn't legitimate. "We have known from multiple reports that the Moran campaign has been conducting a push poll," a Tiahrt spokeswoman said. But Jennifer Duffy, senior editor with the Cook Political Report, told the Pittsburg Morning Sun that the polling firm, Public Opinion Strategies, "has a lot of credibility" and "didn't get that way by doing push polls."