Russian presidential elections aren't rigged in the traditional sense, they're more akin to middle eastern sham elections where only one candidate runs.
Basically the Russian voting process itself is relatively clean/accurate even by western standards. The electoral issues present themselves in the candidate selection process as anyone who might actually be capable of challenging Putin is either in jail or the ground by the time an election rolls round.
The singular exception to this for historical reasons is the Communist party as they have always held such high support in Russia that crushing them would likely trigger civil war. While the idea of Russia electing a president from the CCP in the year 2024 sounds ludicrous they have given him a good run for his money in the past (30% of the vote in 2000 compared to his 53%, and that was with mini-Putin candidates fielded to steal their vote share). In fact historically Putin's dominance over the CCP usually came from the voters in the worse off parts of Russia who blames the CCP for how bad their areas are, but these are the same areas where Putin has spent two years conscripting his cannon fodder and so he is taking no chances for 2024.
