are both true. The mismatch between polls and what people saw comes from the silent majority.
Trump supporter is the most active and passionate group in the election. I think everybody agree with that. That's what people saw in their eyes. For example, Trumps' rallies since 8/1, have total 560,00 people attended. On same period time Hillary's rallies have only total 36,000 people attended and some of them are paid to attend. But, there may be a silent majority. Poll can detect them and find out their voting decisions. So, the explanation for this mismatch is Trump supporters, although active and vocal, are still outnumbered by silent majority and this majority will vote for Hillary.