From US News:
Contrary to popular opinion, Democratic administrations have proved profitable for stock market investors. Since President Barack Obama took office in January 2009, the stock market has been climbing higher in a bullish trend since March 2009, and the numbers are impressive. From the March 2009 low at 666, the Standard & Poor’s 500 index climbed to an all-time high of 2,134 in May 2015, although it was pulling back even before last week’s tumble.
While it may be counterintuitive, the Obama administration is not alone in its positive performance, as history shows stock market returns are nearly twice as strong under Democratic administrations.