On her show Thursday night, MSNBC host Rachel Maddow explained how CNN bent its own guidelines to let Texas Gov. Rick Perry appear in the final debate before the South Carolina primary.

"Will Rick Perry be allowed into that debate? On the surface it appears he does not quality," she noted.

According to CNN’s criteria, only candidates that place in the top four in Iowa or New Hampshire, or have 7 percent support in at least three national polls in January can participant in the debate.

Perry finished fifth in the Iowa caucus and sixth in the New Hampshire primary. But after scouring through polling data, CNN was able to claim that Perry had 7 percent support in three national polls.

Maddow's guest, Felicia Sonmez of the Washington Post, noted that despite Perry's focus on South Carolina, his polling numbers have only gone down.

Watch video, courtesy of MSNBC, below:

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