while downloading Yosemite the power went out and I cant resume the download or get a new one started... sweet! help please?..

While I was downloading the Yosemite upgrade to my iMac7,1 2.8 GHz Intel Core 2 Duo with 2 GB Ram currently running 10.6.8 (I checked and this is a compatible system for the update) the power went out. Sweet. Now it says that the download is paused and I can't get it to start back up. So I poofed the icon off the dock and tried to start another download and I can't get it to start... Thoughts? Thanks