Emily Charnock’s book is indeed about the rise of political action committees (PACs), but the subtitle offers a better sense of the breadth and import of her contribution. By studying how and when groups participated in twentieth-century US elections, Charnock illuminates the path from patronage-oriented party machines and their reformist foes to the ideologically polarized parties of today. She documents steadily increasing involvement of groups in electoral and party politics, noting at each critical juncture the choices that a group could have made but did not. When and why to participate in electioneering, rather than lobby politicians or conduct “education” campaigns aimed at broader public? When to maintain a bipartisan reputation, rather than align with the more congenial major party? By fleshing out the full set of options, Charnock shows how the party system of today reflects strategic decisions by groups pursuing narrow—or at least noncentrist—policy goals. Among the book’s key contributions is its extensive examination of how interest group strategies are shaped by the nature of group goals (change or maintain a status quo) and by group assets (membership vs. money).

The overall narrative is one of increasing interest group participation in electoral politics. Prior to the New Deal, electioneering was considered to be the job of parties alone. Groups that did participate in “politics” (understood at the time as electoral politics) found themselves vulnerable to accusations of corruption or manipulation. Instead, business and farm groups pursued policy goals primarily through lobbying, while the Anti Saloon League (ASL) met with notable success through public “education” campaigns. To the limited extent that these groups did participate in elections, they tried to be perceived as independent—not associated with a particular party, but rather directing support to friendly politicians in both parties. This bipartisan strategy was socially desirable and was used to defend against claims of impropriety. But the ability to work with both parties brought substantive strategic advantages as well—groups benefitted from working with whichever party was dominant in a particular state and from members of Congress in both parties.

Charnock shows that the bipartisan strategy had worked particularly well for the ASL; both parties had dry and wet wings throughout the Progressive Era. But the Democrats’ nomination of prominent wet Al Smith in 1928 led the ASL to support Herbert Hoover, contributing to his landslide victory (including wins in five Southern states). But this short-term success brought long-term costs: By alienating many dry Democrats, the ASL lost valuable relationships when support for Republicans crashed with the stock market.

Charnock argues that, despite this demonstration of the perils of partisanship, Depression Era groups struggled with bipartisanship. The industrial union movement, in particular, was strongly energized by the New Deal, and the Congress of Industrial Organizations (CIO) closely associated itself with Roosevelt’s wing of the Democratic Party. Labor’s Non-Partisan League (LNPL), despite its name, was formed with Roosevelt’s reelection as its sole goal. The LNPL’s “nonpartisan” identity derived from its formal separation from the Democratic Party, not from any real willingness to support Republicans. This independent identity was an electioneering asset, helping to attract voters who wanted to support Roosevelt and the New Deal without considering themselves Democrats.

While the LNLP as a formal organization fell victim to intra-CIO squabbling, Charnock shows that its strategy of independent electoral participation within the Democratic Party gained momentum. The CIO’s Political Action Committee (from which today’s generic term “PAC” derives) was formed to advance an overall liberal agenda within the Democratic Party. Labor had recognized that supporting friendly Republicans was not helpful: Electing more liberal Republicans increased the chance of a Republican majority in Congress, which would certainly be less friendly to liberal goals. The CIO’s support of Truman in 1948 over its longtime ally Henry Wallace cemented its attachment to the Democratic Party. But labor maintained its independent status by greater involvement in primary elections.

As Charnock shows, the success of the PAC model naturally bred imitation. The Americans for Democratic Action (ADA), formed in 1947 with goals similar to those of the PAC, created the first legislative scorecards to address an electioneering obstacle: ignorance on the part of liberal electorates of how their representatives were voting in Congress. The scorecard strategy was widely imitated by many other groups over decades.

Charnock also demonstrates how business groups sought to simultaneously undermine and replicate the success of labor and liberal groups in the electoral realm. A prominent argument against PAC, and its successor Committee on Political Education (COPE), was that labor groups coerced resources from union members who did not share leadership goals. The Business-Industry Political Action Committee (BIPAC) focused on encouraging businesspeople to run for office or otherwise involve themselves in elections. The ACA (later ACU) formed as an explicit right-wing counterpart to the ADA, complete with its own legislative scorecard. But business maintained a bipartisan strategy for much longer. This choice reflected BIPAC’s goals—preserving the bipartisan Conservative Coalition, as opposed to remaking the Democrats into a party of liberalism—and its resources— money over membership.

More broadly, as Charnock argues, groups on the right devoted more effort to public education campaigns to promote patriotism and a free market vision of conservatism. The education-over-electioneering strategy may have been the best option for groups with significant monetary resources, but little in the way of mobilized membership. Over a longer run, the conservative identity that right-wing groups cultivated outside of electoral politics may have contributed to later groups’ efforts to reshape the Republican Party as the party of conservativism.

While political science has recognized the role of group identity in realignments (e.g., Donald Green, Bradley Palmquist, and Erik Schickler’s argument in Partisan Hearts and Minds about White Southerners), less attention has been paid to the intentional role organized interests have played in developing these identities. Charnock shows how labor in the 1930s and 1940s and conservatives in the 1960s and 1970s consciously promoted identities that destabilized existing party attachments, contributing to the realignments that created and ended the New Deal party system.

Some argue that by aligning themselves with parties, groups run the risk of becoming “captured” in the sense that the party will take their support for granted, favoring instead the priorities of unattached swing groups. This logic has some appeal when applied to groups in the sense of unorganized blocs of voters. But Charnock demonstrates how organized groups sidestep the capture concern when they actively participate in the nomination contests that shape party direction. By aligning themselves with a single party, both labor and business gained significantly more influence than if they had retained a bipartisan position. These groups were not captured by their party so much as the parties were captured by them.

Organized groups are notoriously difficult to study—they do not crave publicity like politicians and are not easy to survey like voters. They are highly strategic, making their actions hard to interpret without context. They participate in many domains—elections, lobbying, education, and more. They change names and form as needed to accommodate regulatory efforts or to gain strategic advantage. These challenges aside, the political activity of the organized is what shapes parties and ideologies. Charnock’s book illuminates the micro-details of this process, showing how the polarized party system of today results from the accumulation of strategic decisions by organized, noncentrist groups.