No not the only one. Musk, Thiel, Vance are also working hard and spending tons of money on that.
As far as I can see it's pretty thin. US interence on the other hand has been open.
https://thebostonreport.com/2026/10/11/russia-brazil-electio...
https://russiancouncil.ru/en/news/russian-and-brazilian-expe...