If you really want to track the money in American politics, you have to start by realizing that what you’re pursuing is a moving target.

In fact, one of the oldest arguments made by opponents of campaign finance reform over the years has been is that money, like water, seeks the easiest route. If you try to dam it up in one place – through reform rules outlawing soft money, for instance – it will just change course and gush out somewhere else.

There’s an undeniable logic in that argument, though I don’t agree that it’s a good reason to scrap all reform. Rather, you’ve got to keep pursuing those natural watercourses, bending close to the ground and looking for new spots that might be bubbling up.

In the older and simpler days of American politics, if you gave a campaign contribution to a candidate for Congress, you had every expectation that the money would support their campaign. These days that expectation is often wrong.

For the past few election cycles – particularly since the GOP won control of Congress in 1994 – there’s been a steady increase in what you might call interstate commerce in campaign contributions. You give to a Congressman from Kentucky, say, but the money eventually winds up in Florida or Michigan, or some other district with a tight race.

Check out this Boston Globe article on how Massachusetts Governor Mitt Romney (R) is bypassing federal campaign finance regulations as he prepares for a 2008 Presidential bid.