Former New Jersey governor and U.S. Sen. Jon Corzine, whom President Obama once hailed as an “honorable man” and one of his “best partners” in the White House, has been subpoenaed to testify before Congress about his role in the collapse of the investment firm MF Global.

Corzine was chairman and CEO of the company between March 2010 and Oct. 31, 2011, when it filed for bankruptcy.  An estimated $1.2 billion has not been accounted for, leaving many investor accounts drained.  The FBI and Justice Department are also investigating the case.

The unanimous, bipartisan vote today to require Corzine to appear before the House Agriculture Committee next week sets the stage for tough questioning of one of the president’s top re-election campaign fundraisers and a man who had, until recently, been considered a top pick for Treasury Secretary in a possible second Obama term.

Corzine hosted a private fundraiser for Obama at his Manhattan home in April and has given the maximum individual contribution — $35,800 — to Obama and Democrats for 2012, according to Federal Election Commission records.  He and his family have donated more than $933,000 to Democratic candidates and groups since 1990, according to the Center for Responsive Politics.

The former CEO of Goldman Sachs has also bundled more than $500,000 in contributions for Obama 2012 from his deep-pocket friends and associates, many of whom have ties to Wall Street.

Corzine’s scheduled appearance before the House panel on Dec. 8 comes with potential pitfalls.  If he openly answers lawmakers’ questions, he risks giving information that criminal and civil investigators could use against him.  On the other hand, if he invokes his Fifth Amendment right against self-incrimination, he could appear culpable to some degree.

While Corzine has not yet been charged with a crime, his ties to the failed firm have drawn criticism from Republicans and spurred demands on Obama to return Corzine’s campaign cash.

“In light of the FBI investigation into Jon Corzine’s company, President Obama should immediately return the $500,000 that Corzine raised on his behalf,” Republican National Committee chairman Reince Priebus said in a statement last month.

An Obama campaign official said they would return funds associated with Corzine if he is charged with any wrongdoing in criminal or civil court.

ABC News’ Jason Ryan and Susanna Kim contributed to thsi report.