Via Kevin Drum, we have this interesting data that shows:

What it shows is the difference that the President’s party affiliation makes to the distribution of income during the four years of the president’s term. (The distributional outcomes are shown with one year’s lag.) When a Republican president is in power, people at the top of the income distribution experience much larger real income gains than those at the bottom–a difference of 1.5 percent per year going from the bottom to the top quintile in the income distribution. The situation is reversed when a Democrat is in power: those who benefit the most are the lower income groups. If you are in the bottom quintile, the difference between having a Democratic or a Republican president in office is an income gain (or loss) of more than 2 percent per year! Strikingly, compared to Republicans, Democratic presidents generate higher income gains for all income groups (although the difference is statistically significant only for lower income groups).

The series is from 1948-2005, so it’s not just limited to the last 8 years or the last 2 Presidents. It’s interesting, and a point raised repeatedly in several different studies. Focusing on employment, basic social safety nets, and those core Democratic issues seem to make a difference.