The presidential candidate's session with Lawrence O'Donnell is the second most-watched such event of the campaign season thus far.

Democratic presidential candidate Kamala Harris drew a sizable audience for a town hall on MSNBC on Tuesday night.

The town hall with host Lawrence O'Donnell (which aired as an installment of his nightly show Last Word) delivered 2.21 million viewers, the second-largest audience of any such event in the campaign season so far. It ranks behind only the 2.5 million for Bernie Sanders' Fox News appearance in April.

Harris also drew the biggest audience for any of CNN's candidate town halls to date. Her Jan. 28 event, the first of the campaign, drew a little under 2 million viewers — setting a record for a single-candidate town hall on the network. The CNN town hall also outdrew Harris' MSNBC appearance in the key news demographic of adults 25-54, with 708,000 such viewers to 307,000 for MSNBC on Tuesday.

While it was a solid night for the California senator, the town hall's ratings were not noticeably higher than Last Word's typical numbers. O'Donnell's show averaged about 2.1 million viewers the previous week and is at 2.04 million for the month (through May 28).

MSNBC also finished second in the hour to Fox News' The Ingraham Angle (2.44 million viewers, 374,000 adults 25-54), though it did easily top CNN Tonight (919,000 total, 261,000 in the news demo).

Early polls for the large field of would-be Democratic nominees have Harris among the top four or five behind former Vice President Joe Biden, Sanders and Sen. Elizabeth Warren.