Democrats and “Never Trump” Republicans could not be more emphatic about former Starbucks chief executive Howard Schultz’s possible independent presidential run.

The Bulwark’s editor-in-chief, Bill Kristol, who began advocating for a primary challenge to Donald Trump long before most pundits thought it feasible, told The Atlantic: “One reason my colleagues and I are focused on a Republican primary challenge to Trump — apart from the fact that we’re Republicans — is that it doesn’t present any of the problems of inadvertently helping him by being a spoiler.”

Schultz on the other hand ...

In rare agreement with Kristol, former Clinton adviser Paul Begala remarked on Sunday on CNN’s State of the Union:

“I’m not saying he can’t run. I’m saying he shouldn’t, unless he wants to re-elect Donald Trump. It’s simple arithmetic. I’m old enough to remember, 18 years ago, Ralph Nader called me up. I went and had lunch with him.

“He said: ‘I’m going to get 5 per cent or 7 per cent as a Green Party candidate, have a permanent left party, and Gore will still have enough votes to win.”

I said: “Ralph, the arithmetic doesn’t work. If you run, Bush wins.”

“Howard, if you run, Trump wins, if you run as an independent.” That sentiment is nearly universally shared among Democratic officeholders, operatives and activists. Edward-Isaac Dovere explained why the entire premise of Schultz’s run is flawed.

“Schultz, a lifelong Democrat, would run under the theory that the answer to the political division in the country right now is moving away from party politics,” Dovere writes. “There’s little evidence to support that, as people report being more polarised and partisan, devoted to their own party and demonising the other.

“For all the prominent Republicans who say they don’t like Trump, the President’s overall approval numbers among voters within his party remain sky high, according to polls. Schultz would have to persuade millions of them to abandon the party to vote for him, while drawing enough Democratic votes away from a party that is energised and excited about taking out the President.”

What’s the rationale for a billionaire — who made his fortune selling $5 cups of coffee to upscale consumers — who has never served in public office to run for president? Like the President, maybe he thinks it would be better to run government like a business. Perhaps he is bored and just wants an audience to listen to him pontificate. We’ll see if the backlash is enough to dissuade him from entering the race.

Meanwhile, one 2020 contender is getting plenty of encouragement and interest. After releasing a video last week announcing her intention to run, Kamala D. Harris, the senator from California, held an old-fashioned political rally on Sunday. A really big one — crowd estimates suggested 20,000 showed up — in Oakland, California, to launch her campaign.

Let’s be honest, many in the punditocracy and mainstream media had not considered her at or near the top of the field — not with former vice-president Joe Biden, Bernie Sanders, the independent senator from Vermont, and Beto O’Rourke mulling campaigns. (I would hope they weren’t falling into the trap of taking a non-white woman less seriously as they should, in the same way the post-2018 buzz was all about O’Rourke, not Stacey Abrams.)

Well, whatever the reason for the scepticism, they and her opponents should now be taking her very seriously.

At her rally, she showed she has that “thing” — present, charisma, emotional connectivity — that doesn’t assure victory but without which victory in a Democratic presidential primary is nearly impossible.

She laughs, she beams, she throws familiar glances at friends in the crowd.

She also knows how to construct and deliver a speech. She defined the campaign early in her remarks. The election, she explained, is about “who we are” as Americans. She went through a litany of Trump/GOP ills — eg, child separation, tax cuts for the rich — and after each item declared: “That’s not our America.”

She told the crowd in her quest for the presidency, it was necessary to speak some truths: global warming is real, too many non-white youths are killed by police, and wages aren’t keeping up with rising costs.

Throughout she wove the phrase “for the people” — the phrase a prosecutor announces herself in court (“Kamala Harris, for the people”) — arguing that she “has had only one client” in her life: “the people”. Anticipating criticism of her time as a prosecutor, she argued that in defending the vulnerable against violent crime and homeowners against banks, she continued to act on behalf of, you got it, “the people”.

She hit the administration again and again for sowing division and spreading hate. She declared that she had prosecuted gangs and no “mediaeval wall” was going to solve that problem. On the topic of putting children in cages, she told the crowd that wasn’t border security but rather a human rights violation.

Surprisingly for an opening speech in a Democratic primary, she did not ignore foreign policy entirely. I was pleased to hear her avoid the isolationist rhetoric we’ve heard in the past from some progressives. “I am running to fight for an America where our democracy and its institutions are protected against all enemies, foreign and domestic,” she said.

She later declared that “under this administration, America’s position in the world has never been weaker, when democratic values are under attack around the globe, when authoritarianism is on the march, when nuclear proliferation is on the rise, when we have foreign powers infesting, infesting in the White House like malware”.

It’s a wise move for Democrats to connect our values at home with our foreign policy principles, and to point out that Trump’s trashing of those values amounts to a national security risk.

No candidate will have an easy road to the Democratic nomination, but I would argue that among the declared candidates, none has any better chance than she. She can pump up a crowd, deliver a speech, skewer the President and connect real-life stories to her overarching themes.

That’s not everything, but it sure beats an angry old socialist apologising for mistreatment of women on his last campaign and a whiny guy on a road trip. Maybe it’s time to stop assuming that white men are automatically more viable than non-white women.

• Jennifer Rubin writes reported opinion for The Washington Post