A majority of Republicans and Republican-leaning voters say American colleges and universities have a negative effect on the United States. That is one of the findings of a new report by the Pew Research Center. The report was based on phone interviews with more than 2,500 adults across the United States and the District of Columbia. Over the past two years, Pew found the share of Republicans and Republican leaners who view the effect of colleges and universities positively has dropped 18 percentage points. In the past, a little more than half had a positive view. Now only about one-third do. Democrats and Democratic-leaning independents see the value of colleges and universities very differently. Pew said 72 percent of Democrats and Democratic-leaners say colleges have a positive effect on the United States -- little changed from recent years.