Question: I have a cat that LOVES to play fetch. Most of the time she'll bring me the toy and we'll play for a good 20-40 minutes. However lately she's gotten lazy with bringing the toy all the way, instead dropping it a couple feet away. She doesn't seem to understand that I'm not going to get up every time she does this, but I'm not sure how I can educate her that she needs to bring the toy to me.

I've already clicker trained her for when she can rest on my lap, as well as when she can and cannot have attention. Though whether this helps with further training such as when playing is beyond me.

Answer: 
Never go get it when she drops it part way. She has either become tired of the game and does not want you to throw it any more, or she is training you come pick it up. In either case if she drops it part way back when playing fetch the game is over.
You need to use the clicker to reinforce what you want. Just like with a dog, many people just have an animal that's naturally inclined one way or the other. Either the dog doesn't like to fetch or it does, but either way it isn't trained. My cat fetches as well, but again, it's just something he picked up on his own.

If you truly want it trained, then like keshlam said, you need to train her to target, then work on teaching her to pick up the fetch toy. You work at it incrementally by clicking when she's goes to pick it up. You can either click when she goes near it and only click for closer and closer movements, or you can probably more easily just capture the behavior when you naturally provides it.

If she knows 'target' like come to your hand, then you just get her to pick it up and tell her 'target'. She has to come to your hand to complete the task. You can faze the treat out. I think a good training treat is wet food. Just enough for a single lick. My cat doesn't get wet food regularly and it's a treat he really likes. If you're cat does get wet food, just use his meal as his training aid.