另一個 ...basically, Russia has been the "enemy" of the US for a long time, so people who hate the US/Western "establishment" tend to turn to it for leadership.
And the Kremlin is happy to use these people, fund them, egg them on, give them credibility, in order to destabilize America, in addition to sharing certain values with the current Republican Party (state capitalism, unfettered corruption, marginalization of LGBTQ+ people, hostility to "modern" Western values like feminism, viewing Islam as a threat, etc.).
Or to put it more simply: Russia is a predominantly white, culturally conservative, authoritarian nationalist state where the boundaries between state, business, and the Mafia have been basically erased.