Pretty standard fare for a Cleric/Sorcerer. Throw a water bottle or quicken cast Create Water (if you have no time to prepare the battlefield), then cast lightning spells for massive damage. Maximize against priority target(s). Low Dex is actually quite advantageous in this case, as we want to go later so one of your martials can throw some water around first. You can (and should) wear heavy armor and shields, which will make you reasonably tanky, for a full caster!
In truth, your Race choice will not make or break this build as there’s nothing in particular we’d want. Druegar/Deep Gnome/Drow would work well due to Superior Darkvision, which will help, but anything with Darkvision is good enough. I simply picked Drow as a default option as having darkness on tap is never a bad thing
Sorcerer: Light, Ray of Frost, Shocking Grasp, Fire Bolt; Chromatic Orb, Shield; Storm Sorcery