sentences:  Some academic researchers alleged that the US political system risks drifting towards oligarchy, through the influence of corporations, the wealthy and other special interest groups.Rising income inequality has been linked to political polarization.Krugman wrote in 2014, "The basic story of political polarization over the past few decades is that, as a wealthy minority has pulled away economically from the rest of the country, it has pulled one major party along with it ... Any policy that benefits lower- and middle-income Americans at the expense of the elite – like health reform, which guarantees insurance to all and pays for that guarantee in part with taxes on higher incomes – will face bitter Republican opposition."