Republican presidential candidates Newt Gingrich and Herman Cain will go head to head tonight in a debate styled after the Lincoln-Douglas debates of 1858.

The 90-minute debate will have a time keeper, but no moderator. It will be divided into three parts: Medicare, Medicaid and Social Security. The sexual harassment claims against Cain is the only topic off limits, but Gingrich's history of adultery is presumably off the table too.

The Texas Tea Party Patriots PAC is charging between $200 and $1,000 for tickets, but you can watch for free right here. The event is scheduled to begin at 8:00 p.m. ET.

Watch this live video from C-SPAN, broadcast Nov. 5, 2011.