As Americans head to the polls on Tuesday, law firms across the country are banding together in election protection efforts, readying to staff voter hotlines during what many expect could be a more contentious Election Day than any cycle in recent memory.

Organized by the Lawyers’ Committee for Civil Rights Under Law, more than 100 of the country’s largest corporate firms and legal departments have enlisted volunteers to answer voter hotline calls or do field work. The pro bono work comes as part of the Lawyers’ Committee’s Election Protection program, a nonpartisan effort to safeguard voting rights.