A widening rift in a key constituency courted by the two abortion opponents is unfolding in the GOP congressional primary race in Kansas.

U.S. Rep. Mike Pompeo faces a tough GOP primary challenge from former congressman Todd Tiahrt, who held that position for 16 years before giving it up to run for the Senate. Both candidates in the GOP primary are staunch abortion opponents.

While abortion itself is not a campaign issue, anti-abortion forces have grown into an important voting electorate in south-central Kansas since the 1991 “Summer of Mercy” protests.

In 1994, Tiahrt defeated then-congressman Dan Glickman, an abortion-rights Democrat. Glickman attributes his loss largely to Tiahrt’s grassroots support among the anti-abortion community.

But the anti-abortion community today is deeply divided between the two candidates.