A $300 million slice of Florida’s nearly $200 billion public pension portfolio is invested in Russian companies, even as the pariah nation faces mounting accusations of genocide and other war crimes in Ukraine. Democrats want Florida to divest that tiny part of the fund, arguing the state’s leaders should act swiftly to dump Russian investments. Florida’s holdings include Russian oil producers, mining companies and the country’s largest bank, according to a review from late January. Florida’s chief investment officer says the state’s hands are tied because Russia has blocked foreigners from ma…