What explains the alignment of antiabortion positions within the Republican party? I explore this development among voters, activists, and elites before 1980. By 1970, antiabortion attitudes among ordinary voters correlated with conservative views on a range of noneconomic issues including civil rights, Vietnam, feminism and, by 1972, with Republican presidential vote choice. These attitudes predated the parties taking divergent abortion positions. I argue that because racial conservatives and military hawks entered the Republican coalition before abortion became politically activated, issue overlap among ordinary voters incentivized Republicans to oppose abortion rights once the issue gained salience. Likewise, because proabortion voters generally supported civil rights, once the GOP adopted a Southern strategy, this predisposed pro-choice groups to align with the Democratic party. A core argument is that preexisting public opinion enabled activist leaders to embed the anti (pro) abortion movement in a web of conservative (liberal) causes. A key finding is that the white evangelical laity’s support for conservative abortion policies preceded the political mobilization of evangelical leaders into the pro-life movement. I contend the pro-life movement’s alignment with conservatism and the Republican party was less contingent on elite bargaining, and more rooted in the mass public, than existing scholarship suggests.