Really?
That's like a 900% increase over the typical (random) percent audited by the IRS. That's a higher rate of audit than taxpayers having $5 million in AGI.
http://www.nolo.com/legal-encyclopedia/what-are-the-odds-being-audited.html
That's far too high to make it likely to be a mere coincidence. (Edit: Seems the sample size the IRS examined was fairly small. Need a larger study.)
I would suggest the DIF algorithm used by the IRS to select tax returns for audits be analyzed. It may be targeting contributions to TEA Party type groups by assigning a high score to contributions to such groups. The higher the DIF score the higher the chances of audit.
The above would be automated targeting. There are other ways, but that would likely mean the creation of a task force to specifically identify and target contributors to TEA Party type groups.
I would be interested to know if donors to liberal type groups are experiencing such a high audit rate.
Fern