The House Freedom Caucus is facing an exodus of its most prominent members, casting doubt on its future after years at the center of GOP congressional fights.

More than a half-dozen caucus members are departing Washington to make runs for higher office, meaning next year will lack some of the loudest voices who made trouble for GOP leadership over the last two Congresses. One of the biggest absences will be Rep. Chip Roy (R-TX), a conservative firebrand who lost the Republican nomination for Texas attorney general.