D.C. businessman Jeffrey E. Thompson was charged with two felony counts of conspiracy Monday for allegedly violating federal and District campaign finance laws.

The charges, which relate in part to the 2010 shadow campaign that worked to elect Mayor Vincent Gray, come about three weeks before Gray is set to compete in the District’s April 1 Democratic primary. Gray’s rivals and D.C. voters have suggested that the ongoing federal probe is the biggest obstacle to the mayor’s re-election bid.

Thompson is alleged to have conspired to violate federal campaign finance laws and to submit false filings to the IRS, and to violate District of Columbia campaign finance laws by defrauding the District of Columbia’s Office of Campaign Finance. The violations allegedly occurred between 2006 and 2012 — a six-year span that involves two mayoral campaigns, multiple D.C. council campaigns and several federal campaigns.

In the 2010 campaign, Thompson and his associates allegedly disbursed approximately $668,800 in “excessive and unreported corporate contributions to pay for campaign services and campaign materials in support of a political candidate for the Mayor of the District of Columbia and the political candidate’s principal campaign committee,” according to the 10-page charging document.

The documents also allege that Thompson and his co-conspirators illegally contributed to at least 13 federal candidates, including campaign committees for House and Senate candidates, as well as presidential candidates and a multi-candidate political action committee. Between February and May 2008, the charges allege, Thompson and his associates disbursed approximately $608,750 in excessive and unreported corporate contributions in support of a presidential campaign and a candidate’s campaign committee.

Thompson and his associates would allegedly reimburse those contributions with business payments that were misrepresented as advances, bonuses or consultant fees in the company’s accounting records.

Thompson is scheduled to appear in U.S. District Court for the District of Columbia at 1:30 p.m. Monday to answer to the charges.