It's more so Democrats tend to blow things - i.e. Kerry's campaign that had a backbone of a leaf.
Trump 100% has some things going for him - there are definitely moods that favor him, i.e. non-traditional politician. To ignore or downplay that is a mistake.
But like I've also mentioned, as of July 1, Clinton has a ground game in place that would totally demolish Trump's. In addition, there's also been plenty of talk about fundraising (Trump's campaign just announced a beefing up of their fundraising staff). Established ground game + major cash advantage = hard to overcome. But it's July - there's a long ways to go.
Bragging about polls in June and July means very little. The summer months are often spent framing the campaign and saying well she's winning in all of these polls does nothing to frame her as a candidate or who she's running against. That's a page out of Donald Trump's playbook - bragging about how popular you are in the Republican primary because he was basically a celebrity running.