When Republican Marco Rubio staked out a hard-line position on abortion in the first GOP debate, Hillary Clinton took notice.

Sen. Marco Rubio speaks to guests during a town hall meeting in Cedar Rapids, Iowa. (Photo by Scott Olson/Getty Images)

The Democratic front-runner quickly blasted Rubio's assertion that he did not support exceptions for victims of rape and incest as "Offensive and Troubling."

Clinton aides saw echoes of the controversial comments on abortion that hurt Republicans with women voters during the 2012 election.

Rubio has been backtracking and said he does not back exceptions.