Much has been made about Fox News' and ABC's decisions to limit the number of candidates from their upcoming forum and debate. The main qualm comes from the exclusion of Rep. Ron Paul from the GOP forum on FNC Sunday night.

Now, Politico is reporting that Fred Thompson may drop out "within days" if he doesn't finish better than third place in Iowa, according to several several sources close to his campaign.

ABC will announce its roster for Saturday's back-to-back debate tomorrow. Fox News announced the lineup for Sunday's GOP forum on Dec. 22, with Thompson joining Rudy Guiliani, Mike Huckabee, Sen. John McCain and Mitt Romney. If Thompson drops out, will Paul take the fifth spot?

Fox News has said the limited invites were due to space limitations.