Having it on NBC is like a no chance. The CW would have a better chance then them. NBC is in terrible shape and cutting costs left and right. CBS or ABC is the only way to go, but seems unlikely. The MRC block on The CW is another option.
An online petition probably wouldn't cut it for Fox to bring it back. Something more creative is needed. Jericho fans sent CBS nuts. MEN IN TREES fans made a campaign to save trees. October Road fans created a campaign for
local libraries. Something like that. All of those caught the networks' attention.