This is a much easier way to play the song, with a few minor corrections:

Capo 1


             A                                                    D                     A
Let's Gather round the campfire,and sing our campfire song.
        A                                 B7               E 
Our C-A-M-P-F-I-R-E S-O-N-G song,
       A                                                                 D              A
And if you don't think that we can sing it faster than your wrong,
               B7              B7              E
But it'll help if you just sing along.

The tab for the "Bum Bum Bum" - (relative to Capo)

E:---0----2----4