Two Missouri men on Friday admitted operating a long-running Ponzi scheme that cost more than 90 victims at least $3 million.James “Jim” Johnson, 77, and Darrell Niswonger, 68, each pleaded guilty in U.S. District Court in Cape Girardeau to one count each of wire fraud, securities fraud and investment adviser fraud as dozens and dozens of victims looked on in court. Niswonger also pleaded guilty to four additional counts of wire fraud. Both men admitted engaging in a scheme to defraud that began in 2006.