On Wednesday, the two vice-presidential candidates Sen. Kamala Harris, D-Calif. and Mike Pence will face off for what is surely the most important vice presidential debate in recent memory.

Even before President Trump went to Walter Reed National Medical Center to undergo treatment for COVID-19, it was clear Vice President Mike Pence had a clear task of damage control following Trump’s aggressive performance last week in his debate against Democratic presidential candidate Joe Biden.

While some believe that Biden himself had an uneven performance in that debate, there’s clear evidence that the voters were more disappointed by the president. Analyzing polls of voters about debates is dangerous – voters tend to believe that “their candidate” did better and one should look at the results with that in mind.

Still, in the instant poll conducted by CNN, fully 1 in 4 Trump supporters gave their candidate a bad grade (saying that Biden did better or they both did equally well), while only 1 in 15 Biden supporters gave their candidate a bad grade.

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Moreover, the data from polls conducted after the debate and before the president's positive COVID diagnosis suggested some erosion in Trump's support.

In polls conducted in Florida and Pennsylvania by the New York Times/Sienna College, two-thirds of voters said they disapproved of Trump’s conduct in the debate, where he frequently interrupted his opponent, Biden, and the moderator, Chris Wallace of Fox News.

Pence’s job is further complicated by the need to debate under the shadow of the president’s illness.

On one level, Pence’s job at the debate is the same as it was in his debate against Clinton’s running mate, Senator Tim Kaine, and the same as it has been for his entire term as vice president – provide the emotional and evangelical ballast for the unrestrained and raucously disruptive presidency of Donald Trump.

Four years ago, Pence very clearly won the debate – dominating Kaine, and smoothing the edges off the rough performance of Trump in his first debate with Hillary Clinton.

A CNN “instant poll” that night gave Pence the victory 48% to 42%. Moreover, the Real Clear Politics averages of national polls during the period showed Clinton losing about a full percentage point.

In a period when Trump was clearly bleeding – the "Access Hollywood" tape came out three days later – Clinton wasn’t gaining – and the only ‘good news’ the Republicans were getting came from Pence.

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This year, his challenge is even steeper. Not only does he need to try to stem the erosion from President Trump’s debate performance – he also needs to try to overcome the confusing messages that the Trump White House has been sending about the president’s health.

But even without the haphazard performance by the White House during the president's hospitalization, there’s an overriding problem: the fact that the Trump team’s reluctance to embrace mask-wearing and other elements of social distancing appears may have helped cause the president’s COVID infection.

Can Pence make the case that despite that contradiction, a recovered-from-COVID Trump will be best able to overcome the economic fallout from the coronavirus?

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Arguably, Pence – who is preternaturally able to stay on message with a fervor that would make former President Bill Clinton blush – may be the best Republican to make this case – and certainly the least likely to be thrown off message by anything that Democratic Vice Presidential candidate Kamala Harris seeks to throw at him.

In many ways, Harris has an even harder job than Pence Wednesday night. With the president still recovering from COVID at the White House – and with the Democrats campaigning on “unity” – it’s both emotionally inappropriate and politically unwise to simply attack the president.

At the same time, Harris does need to make the case that the president’s approach to COVID has both made the economic impact of the virus deeper – and may have contributed to many in the White House, among the president’s team and within the Republican Senate ranks – getting infected.

But she needs to do that with a grace that is very challenging for Democrats this year – given the deep antipathy that many of them feel about the president.

During the campaign for the nomination, Harris was one of the few who was able to land a punch on former Vice President Biden – when she attacked him for his position on school busing.

She’s been at her best in Senate hearings when she shows her mettle as a former prosecutor and firmly questions witnesses.

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It’s not clear that that firm approach will work on Pence, particularly given the president’s condition.

The only certainty: both Harris and Pence will present as very polite – but try to deftly unsheathe a stiletto knife.

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