Elections are expensive, and this year's will be the most expensive US midterm elections ever, costing nearly $4 billion. This graphic, based on data from Open Secrets, highlights some of the costliest individual Senate and House races:
Excluding Eric Cantor, who lost the Republican primary in August, the other candidates in the chart are favored to keep their seats in Congress. Mitch McConnell and Kay Hagan face close races, while the other candidates are shoo-ins.
This chart, using the data from the Federal Election Commission (FEC) and represent.us, shows how money affects a candidate's odds of winning:
These numbers count House and Senate elections but not gubernatorial races, and they don't account for money that hasn't been reported to the FEC, leaving out third-party "issue ad" spending, which makes up a significant portion of independent campaign spending.
Of course, money isn't the sole determinant of electoral outcomes. For example, races where a very weak, underfunded challenger loses to a much better financed, more popular incumbent contribute to the figure, but don't really represent a triumph of money so much as they reflect the state or district's underlying politics, and the popularity of the incumbent.