Heat oil in a large Dutch oven or pot to 350 degrees F over medium heat. While the oil heats up, insert the skewers into the hot dogs, leaving at least 2 inches exposed at the end.
In a medium bowl, whisk cornmeal, flour, sugar, cornstarch, baking powder, salt, buttermilk and egg until a smooth batter is made. Pour batter into a tall glass that will submerge the hot dogs.
Dip hot dogs, one at a time, into the glass. Immediately drop hot dogs into the oil. Fry in batches of 2 corn dogs at a time, 2 minutes in the oil, turning constantly. Let cool on a wire rack set over a baking sheet. Continue until all hot dogs have been fried.