Remove Echo from Vocal captured by 2nd and 3rd Mic

Hello,

I'm very new to Audition, but really need to learn it, and fast. I set up three speakers with Lav mics (it's all I have access to right now) and while their vocals are captured great, due to the fact that all three people where around a table, each mic picked up the other person's voice in the background. This lead to a harsh echo once stacked onto each other in Premier. I've tried using a Noise Gate, but it doesn't quite get the job done. Is there another method I can use to clean this up?

Edit: Each mic was recorded to it's own audio track.

Thank you for your time.

-Andrew