Trump would be losing this race in a big way even if there were no pandemic
If you're hoping that a decisive win against Donald Trump and GOP candidates down the ballot would force a reckoning for the Republican Party, you'd likely be disappointed if that outcome comes to pass in November. His base, conspiratorial crackpots and white nationalists, would tell themselves that he was done in by the Deep State and a flood of illegal votes by undocumented immigrants. But more mainstream Republicans would also blame a big loss on factors other than Trump's corruption, bigotry and narcissism. The conventional wisdom would likely coalesce around the idea that the Covid-19 pandemic, and its ensuing economic meltdown, doomed Trump's otherwise strong chances of re-election.
While it's impossible to prove a counterfactual claim, that narrative would almost certainly be wrong. If the pandemic had hit next year, or not at all, Trump would probably be trailing his opponent by as wide a margin as he is now.
Before getting into that, I would note that the Covid-19 disaster and loss of tens of millions of jobs haven't changed the shape of the race by that much. As of this writing, Trump's net approval rate (approval minus disapproval) is at -12 points in FiveThirtyEight's polling average, down from -10.3 points at the beginning of 2020. On January 1, Trump trailed Joe Biden by 5.7 points in RCP's average of head-to-head polls, and now he's behind by 7.7 points. So, as polarized as we are, all of this death and economic pain has only corresponded with the race, and Trump's public standing, shifting by a couple of points.
Does that mean that absent these intertwined economic and public health crises, Trump would be faring better than he is by a couple of points? I think not, and for one reason: If Democrats were running against Trump in an America that was not in the grip of a pandemic, they would be focusing their messaging on his regime's continuing efforts to eliminate the Affordable Care Act (ACA) in its entirety.
Having failed to repeal Obamacare through the legislative process, in June the Trump regime joined a dubious lawsuit brought by Republican officials in several states asking the Supreme Court to strike down the ACA. Trump, who has been promising to enact a comprehensive healthcare plan since the 2016 campaign, has largely gotten a pass on this effort because the Dems have had so many other, more immediate lines of attack to press--from the regime's botched response to the pandemic to Trump deploying unidentified federal troops to quell protests to his corruption of the Department of Justice to his current campaign to delegitimize the vote and hobble the Postal Service.
If Trump were running on a strong economy in a Covid-free election year, that would not be the case. It's safe to say that they'd be hammering Trump for stripping health insurance from 23 million people, killing subsidies and copay-free preventive healthcare and removing protections for people with pre-existing conditions because promising to protect and expand the ACA was the Democrats' central strategy when they won their biggest midterm victory ever in 2018. And that was before this case had worked its way through the lower courts.
It's worth noting that Donald Trump's worst public polling came amid some of the best economic numbers of his presidency in 2017. His net approval rating was around -10 when House Republicans first voted to repeal the ACA, but it sunk to almost -20 in the months that followed, as the fight over repeal moved to the Senate. His numbers only began to rebound to a degree after the GOP had passed its tax-scam, which Democrats also argued was an assault on healthcare.
That the pandemic and ensuing economic meltdown isn't hurting Trump to a significant degree is so counterintuitive that it's hard to accept. It's a testament to the power of the conservative media. But it's unfortunate, because if Trump loses badly in November, the Republican establishment won't attribute the loss--which would be their fourth in a row under Trump in terms of the popular vote--to his mendacity, corruption and bigotry.