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Big Sky, Big Money is a brand new feature length documentary from PBS' FRONTLINE. The documentary is the latest salvo in a war between those who want to spend money influencing political campaigns and those who want know who is spending the money.

Every state has a different set of laws on campaign spending, but Montana has one of the strictest. Or at least had, it's difficult to tell exactly where Montana sits from day to day. Judge's decisions have taken the state from strict rules to no rules and back again in just a matter of weeks.

Despite the judicial dance, a variety of groups are tasked with finding out where all of the political money is coming from.

First and foremost, the office of the Commissioner of Political Practices requires all state candidates to file financial reports on a monthly basis (and even more frequently in the approach to Nov. 6). All of these reports can be found on the office's website once they've been scanned into the system.

Other sites have grown up to track campaign finance money. Through their website, followthemoney.org The National Institute on Money in State Politics tracks spending from both candidates and outside groups in every state. They also happen to be based out of Helena, Montana. Here, one can find a spreadsheet showing the top campaign contributors, or discover if the point of interest (the bulk of donations) for a particular candidate is in Montana or elsewhere.

For federal campaigns, like the presidential election or U.S. Senate races, the website OpenSecrets.org tracks things in a similar way to followthemoney.org. Even with all of this information though, it is impossible to get an accurate picture of campaign spending.

All of the Office of Political Practices reports won't be scanned in until after election day and all of the third party spending will likely never be traceable. What many consider an accurate picture of the campaign likely won't be available until after Christmas. In other words, we won't know where the money came from until after we've cast our votes.