It's June. Of course he can
This.
Absolutely not. Clinton is a terrible candidate who does not excite a large percentage of her base; meanwhile, Trump excites the 25-40% who have been with him since the beginning, plus the other 40-50% of the Party who is galvanized against Clinton. This election could swing in Trump's favor at any moment. If Democrats cared enough to defeat Trump, they would have nominated Bernie Sanders. That said, demographics still favor Clinton and it is entirely possible that she will ultimately succeed in November; in fact, I put her chances at success around 60%.
The people who scream loudest aren't the base. She beat him handily, so clearly the base preferred her. And as the polls show, Democrats are galvanized against Trump as well.