Justin Lamar Sternad, whose failed congressional campaign became the subject of a federal grand-jury investigation, has told the FBI that U.S. Rep. David Rivera was secretly behind his run for office, The Miami Herald and El Nuevo Herald have learned. Sternad, 35, also told authorities that his campaign manager, Ana Sol Alliegro, acted as the conduit between the campaign and Rivera, who allegedly steered unreported cash to the Democrat’s campaign, according to sources familiar with the investigation and records shared with The Herald. Sternad said Alliegro referred to the congressman by his initials, “D.R.,” and called him by the nickname, “The Gangster.”