I'd say it was something to consider even though it's only a surface analysis.
The Capitol Since the Nineteenth Century: Political Polarization and Income Inequality in the United StatesIn the graph below, the polarization between the House Democratic and Republican members is on the left y-axis and the share of income going to the top 1% is on the right y-axis.
Rajashri Chakrabarti and Matt Mazewski
Liberty Street Economics
Federal Reserve Bank of New York
The subject of income inequality has gotten a great deal of attention in the media over the past several months, and polarization and gridlock have been features of the American political landscape for years. We can confirm that polarization has increased over the past thirty-five to forty years, and that it has done so in an asymmetric way, with Republicans moving further from the center than Democrats. And while we find that polarization is only weakly associated with growth, we find a robust association between a widening ideological gap and income inequality.