From this:

The Federal Election Commission has launched an audit into President Barack Obama's record-breaking 2008 campaign.

Individuals familiar with the campaign told Roll Call Friday that the FEC has been investigating the financial records of Obama's previous campaign. The scope of the probe, which began approximately two
years ago, is unknown. Presidential audits typically take years to complete and can cost millions of dollars.

The newly formed 2012 Obama campaign did not deny there was an audit, but a spokeswoman called it a "review."

See the related entries below and the Obama money posts for past coverage, including how the 2008 campaign disabled safeguards designed to prevent fraud. That might have allowed donations from foreign sources.