We looked to see how other invectives hurled by Trump and/or his supporters were working against Biden. In most cases, they seem to backfire on Trump. In all cases, Biden searches are represented by the blue line, Trump searches is represented by a red line. The dotted lines at the end of the some of the graphs represent Google's "forecast" of how often the terms will be searched for in the near future.

Fitness for office issue searches

Trump himself calls himself a "stable genius". Based on Google searches, Americans seem to doubt Trump's self-assessment. Biden vs. Trump: Unfit
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Biden says that the Trump is unfit for office. That seems to be working. Biden vs. Trump: Too old
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The two septuagenarians are about equal on the "too old" front. Biden vs. Trump: Dementia
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Dementia is a more promising line of attack for Trump to use against Biden. Biden vs. Trump: Health Problems
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Biden vs. Trump: Mental Problems
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Trump's Tulsa rally and his long explanation for his dainty walk down a ramp and his two-handed drinking at West Point seemed to cause an increase in people wondering about Trump's mental problems.

Criminal, ethical and moral issue searches

It is not clear what caused people to search for Biden and liar together indicated by the spikes. Perhaps it was something said in the Democratic debates.

Biden vs. Trump: Corruption
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When Burisma was first in the news, people searched for Biden and corruption. It gained a resurgence during Trump's impeachment hearings, then the issue died off as it related to Biden.

Biden vs. Trump: Rape
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Biden vs. Trump: Sexual Assault
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The rape and sexual assault lines of attack worked against Biden as Tara Reade rolled out her salacious accusations against Joe Biden which culminated in an accusation of digital penetration. The searches related to Biden petered out when Reade's story was more thoroughly vetted. Reade is being investigated for making false statements under oath on related matters. Bringing up anything to do with inappropriate sex hurts Trump more than Biden. Evidently aware that he lives in a glass house, Trump himself has mostly steered clear of the topic.

Biden vs. Trump: Racist
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Biden's name was connected to the term "racist" mostly after his "you ain't Black" interview with Charlamagne Tha God. But Trump trumped him quickly in that category with his not so empathetic reaction to George Floyd's death and the subsequent protests.