Can I make Corn Dogs in advance?
You can make them ahead of time, you can partially fry them after dipping them in the batter and frying them until they are a light golden color (enough the batter wont stick to each other). As you complete them, put them in the freezer and when ready just pop them in the hot oil (defrosted of course.) This will not only let you get them ready to go ahead of time but will also shave off time in between serving each corn dog. As with anything before serving to a large group though, test it ahead of time to make sure nothing funky happens. 

Also, what kind of fryer do you have, it may very well be the culprit here if you are not using a restaurant quality one. If you aren't, there are a couple of decent options. Let me know what you are using, and I will get back to you on what you can do instead.