Tips to Meeting Presidents and Presidential Candidates in NH?

So if you love politics, New Hampshire is certainly one of the best states in which to live; with our "first in the nation" primary each presidential election year, we always get every candidate running from every party and each president running for re-election (or trying to help a fellow party candidate win).

Parties aside, if you're like me and simply want to see as many varied candidates as possible up close (meaning a handshake and selfie) any great hacks?

Many have mentioned that when it comes to these events (like the one coming up with former Vice President Biden in Portsmouth July 12) camping out early, knowing a person at the venue may all not be enough.

Any long time residents/fellow political junkies have any great stories of "Forrest Gump moments" meeting candidates and/or leaders up close here in the Granite State?