The sixth Republican primary debate will likely see as few as six candidates on the main stage, relegating candidates like Rand Paul and John Kasich to the undercard round, according to criteria released by Fox Business Network on Tuesday evening.

The Jan. 14 primetime debate will include the top six candidates based on the average of the five most recent national polls, as well as those who finish in the top five in Iowa or New Hampshire. Polls must meet Fox Business standards and be released before January 11 at 6 p.m. ET.

At present, the same six candidates are at the top of all three polls. But a Fox Business spokesperson confirmed that the main stage could include more than six candidates depending on where things stand in mid-January.

The Jan. 14 debate will also see the return of the undercard round. Candidates must clear 1 percent in at least one of the five most recent polls to participate in that debate.

The Fox Business debate will be held in North Charleston, South Carolina.

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