Obama's Job Approval Among Democrats is Falling

13-point drop since last December

PRINCETON, NJ -- Barack Obama's job approval rating among Democrats, his core supporters, has averaged 78% so far in September after being at or above 80% each month since December 2011, including a recent high of 91% in December 2012.

The 13-percentage-point decline in Democrats' approval rating for the president since last December exceeds the nine-point drop, from 53% to 44%, among all U.S. adults over the same time.

Democrats' approval rating of Obama has either declined or held steady each month this year. It last showed an increase in November 2012.