"The Logic of Secession"
Yes, secession was tried once before unsuccessfully, say opponents; however, conditions were ENTIRELY different back then. In a very real sense, it also has been a successful venture in this country---for example, Kentucky and West Virginia "seceded" from Virginia.
Following is a website that seems to be the most professional and informative regarding the political strategy of peaceful secession. [If nothing else, please view the series of short video clips.]