Rep. Barbara Lee, a progressive icon from Oakland, has been viewed as a likely choice as well, and recently led in a University of Southern California poll on who Newsom should pick.

Long Beach Mayor Robert Garcia, who would be the first Latino and the first openly gay senator from California, if tapped, is a rising star in the Democratic Party and has recently catapulted up the shortlist, according to people close to Newsom.

State Senate Pro Tem Toni Atkins of San Diego, who is also LGBTQ, would be another historic choice and is viewed as a contender.

Former Gov. Jerry Brown has speculated that Newsom would be more likely to pick a statewide officer for the seat, because that would allow him to name both the next senator and a powerful state officeholder's replacement as well.

Aside from Padilla, that puts Attorney General Xavier Becerra, who is not as close to Newsom, Treasurer Fiona Ma, and State Controller Betty Yee — all candidates of color — in the mix.

Both Yee and Ma, have already indicated their interest in a future run for governor, as has the state's first female lieutenant governor, Eleni Kounalakis, who also is viewed as having potential with the incoming Biden administration.

Rep. Katie Porter, a freshman who is one of the party's more robust fundraisers, has strong support among younger voters, as does Silicon Valley Rep. Ro Khanna, who is of South Asian descent and a favorite of progressives who bolstered his profile as the former national co-chair of the Bernie Sanders presidential campaign.

Other names being buzzed about in California include two prominent mayors, San Francisco Mayor London Breed, and Oakland Mayor Libby Schaaf.

Newsom said this week he wouldn't formally begin the process of making a a decision until the election was formally called. But he gave some hints about the direction he was leaning, noting that names specified in recent POLITICO rundown was "a good list,'' though he joked that maybe "30 or 40 more" might be added to it.

The intense lobbying for his appointment to fill Harris’ Senate seat was "not something I’d wish on my worst enemy," he quipped on Tuesday.

"You create enemies in this process; you don't just make great friends — and it's a vexing decision," Newsom said. "It’s a challenging one. It’s also a presumptive one ... some people are voting for Kamala Harris, so is [the appointee] in her image?"

Other considerations include whether Harris' replacement would be able to hold the seat at the end of her current term, which expires in two years — or if he should pick a "placeholder" that would allow an even playing field given how someone may hold the seat for decades.

Newsom said he is being lobbied day and night by Democrats, and joked they're getting creative in attempting to get his attention.

"You know there's phone calls, there's emails," he said. "People just happen to show up certain places. They want to babysit your kids, they offer to get groceries, get coffee."