A former Iowa state senator has pleaded guilty to federal charges that he accepted money from the Ron Paul 2012 presidential campaign to switch his endorsement from Rep. Michele Bachmann (R-Minn.), who was also running for the GOP White House nomination. Kent Sorenson, of Milo, Iowa, has been at the center of accusations that he was paid for his endorsement, first by the Bachmann campaign and then by the Paul campaign, in late 2011. Sorenson switched his endorsement at the last moment before the Iowa caucuses in the 2012 race, but vehemently denied he had been paid to do so. Last year, OpenSecrets blog published emails alleged to be between Ron Paul campaign officials and representatives of Sorenson discussing Sorenson’s demands for payment. Later, audio recordings emerged in which Sorenson discussed how a Paul operative named Dimitri Kesari offered him a $25,000 check, written in the name of a jewelry shop owned by Kesari’s wife, to switch sides.