Last night's GOP CNN/YouTube debate was the most-watched debate of this cycle, topping even the Democratic debate in Las Vegas on Nov. 15 which had been the most-watched. The numbers from Nielsen (Live +SD):

• 8pmET - 10:11pmET
P2+ — 4,486,000
A18-34 — 516,000
A18-49 — 1,300,000
A25-54 — 1,540,000
A55+ — 2,668,000

>More: The press release from CNN is after the jump...

CNN's Republican YOUTUBE Debate is the Most-Watched Primary Debate in Cable News History!

CNN Has the #1 and #2 Highest-Rated Primary Debates in Cable!

Last night's CNN YOUTUBE Republican Primary Debate was yet another record-breaker with more than 4.4 Million viewers tuning into CNN. These deliveries exceed ALL other primary debates in Cable News History IN ALL DEMOS!

(8-10:11p)
P2+ 4,486k
P18-34 516k
P18-49 1,300k
P25-54 1,540k
P55+ 2,668k

Nearly 5 Million viewers tuned in on both CNN and Headline News (simulcast) for last night’s Republican Primary Debate (4,900k).

CNN's Democratic Primary Debate at UNLV on November 15 is the second highest-rated debate in history with 4 Million total viewers.

Source: Turner Analysis of Cable Fast National Data