Wednesday night was the most-watched night in the history of CNBC, with much of the viewership driven by the GOP presidential debate.

The network announced today that the debate delivered 14.0 million total viewers, based on Nielsen Fast National Ratings. The telecast averaged 3.9 million viewers in the key news demo of adults 25-54, and 3.4 million adults 18-49, ranking as CNBC’s most-watched telecast of all time.

Leading out from debate coverage, CNBC continued to score strong numbers, with an episode of the original series “The Profit” becoming the most-watched telecast of an original series in CNBC history. The program, which follows serial entrepreneur and investor Marcus Lemonis as he tries to save struggling businesses, delivered 1.9 million total viewers, with 820,000 in 25-54 and 708,000 in the 18-49 demo.

The “undercard” GOP debate, which aired at 6 p.m. ET, averaged 1.6 million total viewers, and the 7 p.m. debate warmup show “Your Money, Your Vote” pulled in 3.3 million.

The turnout shattered a number of previous marks by wide margins.

“The Republican Presidential Debate averaged 3.5 times as many total viewers and 1.8 times as many adults 25-54 as the previous record holder (2002 Winter Olympics telecast on 2/22),” the network said in an announcement, adding: “The Republican Presidential Debate averaged 4.2 times as many total viewers and 3.9 times as many adults 25-54 as the 2011 CNBC Republican Presidential Debate.”