Briggs 23hp v twin won't start without a shot of carb cleaner

My Husqvarna 48" riding mower with a 23 hp Briggs engine which I bought new a couple of years ago, has never started easily. If I want it to start without running down the battery, I have to give it a squirt of carb cleaner, then it starts right up. Once it is running, it works fine, and will start right up if I turn it off. What could be the problem?
I'm new to this forum, so if tis has been already answered, I apologize, but I don't know how to search the forum . . . Yet!
Tex.

Briggs 23hp v twin won't start without a shot of carb cleaner