In the 2020 election cycle, outside spending in U.S. federal elections exceeded $2.6 billion, according to the Center for Responsive Politics. This amount was nearly eight times that in 2008, the last presidential election cycle before the landmark U.S. Supreme Court decision in Citizens United v. Federal Election Commission. Drawing on academic research, media reports, and expert opinions, Henrik M. Schatzinger and Steven E. Martin in Game Changers provide an accessible and comprehensive summary of how the flood of money unleashed by Citizens United transformed the landscape of campaign finance in the United States.

A significant portion of this book is structured to document changes induced by Citizens United across the domains of campaigning (for example, presidential versus congressional elections). It may be helpful to synthesize this body of evidence under a general framework of how Citizens United altered the rules of the game. At the risk of oversimplification, I think the key regulatory changes due to Citizens United