(CNN) - I have long argued that coronavirus was the only election issue that really mattered. History tells us that when a non-economic issue is topping the list of the nation's problems in a presidential election year, then the candidate who is trusted most on that issue almost always wins.
Coronavirus is raging nationwide with only five days to go until Election Day. For President Donald Trump to win reelection, he's going to have to somehow do so even as cases are on the upswing in almost all the key battleground states that he won four years ago.
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There were 10 states Trump won by less than 10 points in 2016: Arizona, Florida, Georgia, Iowa, Michigan, North Carolina, Ohio, Pennsylvania, Texas and Wisconsin. In nine of these states, there was a daily average of at least 15 new Covid-19 cases per 100,000 people over the past week. The lone exception was Arizona, according to The New York Times, where there were 14 new cases per 100,000 people.
Wisconsin, on the other hand, had a high of 72.5 new cases per 100,000 people. This was the highest number among the battleground states and was third in the nation.
The high number of coronavirus cases can't possibly help the President in the closing stretch of the campaign. Trump seems to be doing worse in communities where Covid-19 deaths are higher, according to one study.
This could help to explain at the margins why Biden is doing so well in Wisconsin right now. Remember, Trump won the state by a little less than a point in 2016. Biden's up by an average of 8 to 9 points. In one (likely outlier) poll released on Wednesday, Biden was up 17 points among likely voters.
But even if there were no direct link between coronavirus activity in a state and Trump's standing, the mere discussion of the pandemic is not a good thing for Trump. Our CNN/SSRS poll on Wednesday showed that Biden was more trusted to handle the coronavirus by 57% of likely voters. Trump came in at just 39% in the matchup.
Biden has never trailed Trump in any CNN poll on who was better to handle the coronavirus crisis.
View 2020 presidential election polling
Trump, of course, has seemingly been arguing that the media have been talking about coronavirus too much. It's the voters, though, who seem to be seeing the numbers and think it's a big problem.
Coronavirus has been -- or has been statistically tied for -- the nation's top problem in every Gallup poll since the spring. During that same period, Biden has maintained a north of 5-point lead in the horse race against Trump.
It's possible that a different president might be able to change the subject through his words. The big issue is Trump has no credibility on the subject. A number of polls have shown that he simply isn't trusted to relay information about the virus.
This goes back to a deeper problem for Trump: He isn't trusted, period. A majority of Americans don't think he is honest and trustworthy. A majority of Americans believe his opponent, Biden, is.
In a year in which a global pandemic is gripping the nation, a president who has presided over a country where the virus continues to disrupt daily life and whose word is not trusted is likely to lose.
And that's exactly where we stand with the election closing in.