“I’m exploring. I’m looking at whether it’s going to be a possibility,” Testerman told the paper last week.

Testerman, a conservative activist who founded a nonprofit and political arm that advocates for conservative issues in state politics, came in third in the 2010 gubernatorial primary with 10 percent of the vote.

She hasn't yet decided on whether to run, and has no timeline for her decision, but Testerman filed paperwork last Monday setting up an exploratory committee.

The social conservative would likely run to the far right in a primary. She's an outspoken opponent of gay marriage and civil unions for gay couples, and previously said that “could promote the acceptance of a behavior that is jeopardizing the health of our children," according to the Monitor.

Former state Sen. Jim Rubens and state Senate Majority Leader Jeb Bradley are looking at a possible run for the GOP nomination as well.

Republicans believe Shaheen could be vulnerable in 2014, citing the traditionally purple tint of the state and polling indicating ObamaCare is unpopular there. Shaheen, however, continues to post strong approval ratings, and the lack of an official Republican challenge is an indication of her relative strength for reelection.