Managed to destroy his second base once but he rebuilt soon after. Eventually I mass attacked him with Vikings and left my ground units to cover my base. Destroyed what I assume to be most of his units along with his second base and he quit. I completely exhausted 2 bases of mine, had 2 others. I think I was able to win with my extra SCVs and constant calldowns of MULEs. I had 8 MULEs mining at once.