Who needs Donald Trump? CNN's second debate on Tuesday night — and the first among the Democratic field — lured 15.3 million viewers, according to Fast National ratings from Nielsen. That's a best for the Democratic party, eclipsing the 10.7 million record on broadcast and the 8.3 million for CNN — both in 2008.

That's south of the recent GOP numbers, but, to be sure, the ratings for the first two GOP debates were an anomaly. Fox News set a record with more than 25 million viewers for the first GOP debate on Aug. 6. And 23 million viewers watched the second GOP debate on CNN on Sept. 16. But last night's debate is still likely to pull in healthy numbers compared with Democratic debates from previous election cycles. The highest rated Democratic debate on cable is still CNN's January 2008 face-off between Barack Obama and Hillary Clinton that pulled in more than 8 million viewers.

The disparity is due to a Democratic field that has generated far less excitement among its base than the volatile and much larger GOP field. But the Democratic debate did include some memorable moments, like when Vermont Senator Bernie Sanders, in an expression of solidarity with front-runner Clinton, quipped: "The American people are sick and tired of hearing about your damn emails."

He was referencing Senate Republicans' continued digging into Clinton's use of a private email account when she was Secretary of State. The issue has become a political football in Washington as the Republicans seek to uncover deleted emails that may shed more light on the embassy attacks in Benghazi in 2012. Sanders went on to list a number of pressing issues facing the country including income inequality.

"Enough of the emails," he concluded. "Let's talk about the real issues facing America."

Clinton, who was positioned next to Sanders on the dais, then shook his hand, prompting voluble applause from spectators in the hall.