Who's spending big, and where, in most expensive election cycle ever

Spending for the current midterm election cycle is accelerating as the date for Election Day approaches. Billions of dollars are being deployed to influence the outcome of the races that will determine which party controls Congress in the coming year.

This cycle is currently on track to be the most expensive in history. Political analysts are tracking the distribution of these funds to understand the strategic priorities of the groups and campaigns involved in these contests.