Don't get too excited. It's just one poll. It reflects a convention bump that could - but won't necessarily - be wiped out by a potential bump for Hillary at the end of this week. It's a tracking poll, which means it's reflects a rolling average of several days rather than a snapshot in time. And it's July. Nothing is being decided now.
But if you want the Trump-Pence ticket to win in November, there are plenty of reasons to find the following encouraging:
Here's why a 47-40 lead for Trump in a tracking poll represents something to build on: