[Read the full story about Ms. Harris’s announcement.]

That first part, many observed, seemed to be a jab in part at the billionaires in the race like Tom Steyer, a fellow Californian who is funneling lots of his own money into his campaign.

As of Tuesday, Mr. Steyer was the only resident of the Golden State who is set to appear in this month’s presidential debate in California — at Loyola Marymount University in Los Angeles on Dec. 19, to be precise.

Ms. Harris had already qualified for the debate. So far, she was the only person of color to do so in a field that has been touted as the most diverse ever. (Although, as my colleague Jennifer Medina reported, the symbolism of barrier-breaking campaigns hasn’t been much of a propellant for candidates like Ms. Harris and Julián Castro, who would be the first Latino nominee.)

[Who’s in and who’s out of the debates?]

The timing of Ms. Harris’s announcement had to have been a bit awkward for Gov. Gavin Newsom, who, on Monday afternoon tweeted that he was looking forward to joining his state’s junior senator “out on the trail.”

Going forward, his endorsement is up for grabs, as are those of other California leaders who had already thrown their support behind Ms. Harris, and those who haven’t yet endorsed.