It took all of two weeks for Donald Trump’s support to collapse. In mid-to-late July he began to pull ahead nationally. The last three major national polls have shown him trailing Hillary Clinton by 9, 10 and 15 points.

The RealClearPolitics polling average has Trump 6.8 percentage points behind Clinton nationally. In the Huffington Post average, it’s 7.5 points. Many supporters are wondering went wrong after he beat 16 other Republicans in the primaries, suspecting that perhaps the anti-Trump media has skewed the polls now that he is up against Clinton.