I think OhRedhead may be right, and that you might want to think about tweaking your dynamic - reversing it.
What I suspect is happening is that you are doing something "bad" (being rude, lazy, disrespectful etc) which you feel warrants a spanking. Makes sense, you're a spanko. You may even behave this way to get a spanking, on purpose.
But.
If she's not a spanko, these behaviors, intentional or not, are not going to put her in the mood to do you a favor (which spanking you is, to her). Quite the opposite, she's going to be annoyed/irritated/pissed. And catering to your need, one she fundamentally doesn't get or share, will be the last thing on her mind. Moreover, she may be concerned that if she does spank you, because you are a spanko this will serve only to create more negative behaviors. In other words, you getting what you want will make her life less joyous and peaceful.
As OhRedhead suggests, if you have a dynamic where a sound spanking is a reward, then you will be a wonderful husband and also get your butt blistered.
Anyway, what do I know, just some thoughts that are worth precisely what you paid for them.