WASHINGTON — Thursday night’s Democratic debate was billed by many in advance as a head-to-head clash between the two early 2020 polling frontrunners, former Vice President Joe Biden and Vermont Sen. Bernie Sanders.

Instead, Sanders was reduced essentially to an onlooker as Sen. Kamala Harris of California elbowed herself in as Biden’s prime bete noir, the only black candidate on the stage going after his positive reputation on the issue of race.

While recognizing Biden’s record as a civil rights champion, Harris deftly played a personal card by identifying herself as young beneficiary of school busing in California, which Biden opposed in his own state of Delaware in 1977.

The ploy drew Biden’s controlled but obviously jolted reply as a “mischaracterization” of him. He also rejected her implied allegation that he had tolerated or ignored the segregationist record of Southern Democratic senators with whom he worked on other issues. He noted defensively that he had served as a public defender in his early career as a lawyer.

Harris’s double whammy at Biden went to the heart of his current defense as a veteran legislator who valued and continued to advocate reaching across partisan divides to achieve the common good. In so doing, she made a case to be elevated to stature as a serious challenger to the former veep for the 2020 Democratic presidential nomination.

Other Democratic contenders such as Mayor Pete Buttigieg of South Bend, Ind., also benignly chipped away at Biden as a questionable voice of generational change in the party. His remarks suggested that Biden at 76 was vulnerable to allegations that he doesn’t “get” how social mores have changed in gender relations.

In all, the second night of the Democratic twin bill was a bit of a wake-up call for the early frontrunner in the polls. Biden pushed back against Sanders’s continued advocacy of Medicare For All, which would replace the Affordable Care act, aka Obamacare. Defending it reinforced his moderate-to-liberal posture on the centerpiece legislation of the Obama-Biden administration years.

The first round of multiple candidate debates itself turned out to be cumbersome, for all the even-handed intentions of the sponsoring Democratic National Committee. Hitchhikers on the process such as inspirational speaker Marianne Williamson and technology guru Andrew Yang were fish out of water, and should be fished out before the next round.

Party optics were well served by having three women contenders in the mix for the second night of the first round. But with Massachusetts Sen. Elizabeth Warren already cementing her position as a serious entrant and Harris now enhancing her own in her pivot against Biden, New York Sen. Kristen Gillibrand may hard-pressed to survive for the long run.

While I’m at it, I’d like to cast a vote, for what it’s worth, for a similar weeding out of the field of five or more television interrogators of mixed competence as analysts of the 2020 political scene. Some of them seem to fancy themselves as current-day Walter Cronkites, David Brinkleys and John Chancellors, but mostly are devoid of the track records for objectivity of those past worthies.

The best, or worst, is yet to come in the second and third rounds of these DNC show-and-tells of Democratic presidential wannabees in July and August, with the countdown to state caucuses and primaries to follow early next year.

For the party the prime objective remains removing the yoke of Trumpism on the land, with Joe Biden continuing to argue he is the best person for the job by virtue of his temperament and political experience.

Others, including Sanders, Warren and Harris, are focusing on the ideological and political struggle over the direction of the party, as an increasingly vocal progressive wing tugs it increasingly to the left. Goals include more and better social services for working men and women of all backgrounds.

But for now, the fate of the party of FDR, Kennedy, Clinton and Obama hinges on getting Donald Trump out of the Oval Office.

Jules Witcover’s latest book is “The American Vice Presidency: From Irrelevance to Power,” published by Smithsonian Books. You can respond to this column at juleswitcovercomcast.net.

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