Trump received 74 million votes.
The NRA, which has proven to be infiltrated by russian assets has about 5.5M members so that's almost 7% right there. https://www.finance.senate.gov/ranking-members-news/wyden-unveils-report-on-nra-ties-to-russia-findings-show-nra-misled-public-about-2015-moscow-trip#:~:text=New%20evidence%20that%20NRA%20insiders%20may%20have%20violated%20U.S.%20sanctions,pursuit%20of%20personal%20business%20opportunities.
In 2021 there were about 20M users of Parler which amplified russian propaganda: https://www.forbes.com/sites/jemimamcevoy/2020/10/01/report-fbi-catches-another-russian-made-fake-news-site-targeting-us-voters/
There's probably some overlap, but with just two instances we've seen how over 20-25M right wingers (1 out of 3 trump voters) are subject to russian propaganda.
It is not just bots but an infrastructure of heavy investment in mass media that mislead americans. Fox News, NAEBC, Tucker Carlson, the NRA, Breitbart and then you can add in the bots on social media.