One of the cool things that Baseball Prospectus offers is a day to day history of each teams playoff odds. While their odds are clearly inferior to mine :), this is a very cool feature.
When graphed out, these allow you to see the peaks in allies that each team has throughout the season. Given the flurry of trades that the Cardinals have made over the past couple of weeks, I thought it would be cool to see how their odds have progressed, and how that compares to some other teams in their division:
If it's a little fuzzy, you can click on the graph for a larger view.
These are taken from BP's PECOTA adjusted playoff odds page. For the sake of making a better comparison, I chose to only graph each teams odds of winning the division.
You can see three distinct trends for these teams. The Cubs started off as the preseason favorites; however, they experienced a slow and steady decline throughout the year until a recent upswing in their odds. The Brewers started off as a longshot, but were able to work they way into the lead before plummeting over the past 20 games. Interestingly, their playoff odds trend resembles a bell curve. The Cardinals, on the other hand, have been slowly but surely working their way up, and are now the divisional favorites.