According to The New York Times, Senator Kamala Harris's campaign unraveled long ago (at least in political time) due to her own clumsy campaigning and florid dysfunction among the campaign staff she oversaw.

According to Harris today, she "simply doesn’t have the financial resources we need to continue." But, also, she wants to be clear that she is "still very much in this fight."

Some context: Harris only had a few days to get out before her name would appear on the California ballot, which gets mailed to voters in early February. Getting crushed in California would have been devastating, and set her up for a challenge in 2022 for her reelection.
— Ryan Grim (@ryangrim) December 3, 2019

Some people on the left found Harris stunning, while others griped that she's "a cop." (Harris was never a police officer, but she was Attorney General of California for a while, and in the presidential race that earned her the opposite of the Bob Ferguson treatment.)

With Harris out, next time the liberal contenders gather "Democrats may have an all-white debate stage," notes The New York Times—despite the party "beginning the primaries with the most racially diverse field in history."