• Billionaire hedge fund manager Jim Simons, a Democrat who’s one of the major financiers of the Senate Majority PAC — which has run a host of ads attacking Republican U.S. Senate nominee Thom Tillis — is under siege by senators of both parties — and the IRS. The Washington Free Beacon reports that the Simon-run Renaissance Technologies hedge fund reportedly used accounting gimmicks to avoid $6 billion in federal taxes.

• A New York Times blog explains how Sen. Kay Hagan and national Democratic officials have used the Wake County Democratic Party to bypass all the turmoil inside the state party.

• Meantime, The Washington Post reports on a new Democratic poll showing that red-state incumbent senators, including Hagan, face additional troubles in part because President Obama’s popularity is lower in their states than in the nation as a whole.

• Freedom Partners, a group funded in part by the Koch Brothers, announced a $2.8 million ad buy in North Carolina to support House Speaker Thom Tillis’ campaign against Hagan.

• Rep. G.K. Butterfield, D-1st District, has joined more than 30 other House Democrats in forming a special caucus to lobby Republican governors (including Pat McCrory) to expand Medicaid under Obamacare.