When Vice President Kamala Harris takes the stage in Philadelphia on Tuesday, she will have to debate her toughest opponent of the election cycle – and it is not former President Trump, a columnist argues.

Harris' "most complicated antagonist," according to a New York Times opinion piece published on Thursday, is President Biden, a man she must both deflect from and defend.

"Harris will have to face off against President Biden — his record, his shifting public approval rating and their intertwined legacies — from now until Election Day. Her supporters are eager to watch her 'prosecute the case' against Trump in their debate. But when it comes to the Biden years, Harris is both prosecutor and defendant, reformer and institutionalist, contrast and continuity. And that's a harder sell," Times opinion columnist Carlos Lozada wrote.

Describing her dilemma as "simple but awkward," Lozada suggested that Harris can either own the accomplishments of the Biden administration and risk criticism on inflation and the border, or distance herself and appear as a "nonfactor" as vice president.

TRUMP-VANCE TICKET HAS DONE COMBINED 39 INTERVIEWS SINCE LAST MONTH COMPARED TO ONLY SIX FOR HARRIS-WALZ

it's a margin of error race between Vice President Harris and former President Trump

Democratic presidential nominee Vice President Kamala Harris and President Joe Biden arrive at a campaign event at the IBEW Local Union #5 union hall in Pittsburgh, on Labor Day, Monday, Sept. 2, 2024. (AP Photo/Jacquelyn Martin)

"Donald Trump seems to wish he could still run against Joe Biden. Kamala Harris probably wishes she didn't have to," Lozada added.

CNN reported Wednesday that Harris accepted the rules of the upcoming ABC debate after receiving separate "assurances" that mics could be turned on during the debate and the moderators would explain unheard exchanges.

The Harris campaign sent a letter to the network officially accepting the debate rules while still complaining about the terms.

HARRIS, TRUMP AND 2024: DEBATES, POLICIES AND PRESS SCRUTINY ARE CRITICAL NOT OPTIONAL

Former President Donald Trump

Former U.S. President and current Republican Presidential nominee Donald Trump speaks about the economy, inflation, and manufacturing during a campaign event at Alro Steel on August 29, 2024 in Potterville, Michigan.  (Bill Pugliano/Getty Images)

"Vice President Harris, a former prosecutor, will be fundamentally disadvantaged by this format, which will serve to shield Donald Trump from direct exchanges with the Vice President. We suspect this is the primary reason for his campaign's insistence on muted microphones," the letter read.

After Biden dropped out of the race in July, the Harris campaign insisted on moving forward with the previously agreed upon ABC presidential debate. However, weeks after Trump acquiesced, the Harris campaign began trying to change the rules to make the microphones live throughout the event.

Though Trump expressed openness to the idea, both he and his campaign attacked the Harris campaign for suddenly demanding changes.

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Trump frequently interrupted and spoke over Biden when they first debated in 2020 and was widely seen as the loser of that exchange. His vastly improved performance at their meeting in June, coupled with Biden's dismal showing, helped lead to the latter's exit from the White House race.

Fox News' Lindsay Kornick contributed to this report.