The fourth debate of the 2024 Republican presidential primary will be held in Tuscaloosa, Alabama, on December 6 and require higher polling and donor thresholds for candidates to qualify, according to a memo posted by the Republican National Committee on Friday.

The new criteria will be an increase from the thresholds set for the upcoming third presidential debate, where 70,000 donors were required and the polling criteria required candidates to reach at least 4% in two national polls or in one national poll and two polls from separate early-voting states.

Based on CNN’s assessment of the criteria for the November debate, Florida Gov. Ron DeSantis, former South Carolina Gov. Nikki Haley, former New Jersey Gov. Chris Christie, and entrepreneur Vivek Ramaswamy have met the thresholds for participation in the debate. It’s not clear yet whether North Dakota Gov. Doug Burgum and Sen. Tim Scott of South Carolina will meet those thresholds in time. The field has been shrinking in the past few weeks, with the most prominent candidate to drop out being former Vice President Mike Pence.

The New York Times was first to report on the memo.