Want to get an influential person to come and see your show and hear your music?
Then why not treat them to some food? Really!
Indie artists never think about targeting one or two influential local music journalists or radio DJs and offer to comp their night.
Sure, there are still no guarantees that the person you invite will like your music, but I'd bet on this more personal approach any day over some "get successful quick" campaign that sends unsolicited emails to the world.