Trouble downloading Mountain Lion from the App Store

Hi!

I am currently running snow leopard 10.6.8. I have updated all of my software, run time machine, and backblaze. I have purchased Mountain Lion through the App Store, but have tried to download it three times without success. I get a pop up window about 3/4 of the way through the download that says "download failed" , check our internet connection. I have checked it in the Systems Preferneces and I have green buttons on both the ethernet and wireless connections.

Any suggestions for how I can successfully download and install Mountain Lion?

Thanks!

Kim