A conservative super PAC is taking to the airwaves with a new commercial criticizing Republican Senate candidate Liz Cheney's comments on gay marriage.

Cheney said earlier this year that she is "strongly pro-life and I am not pro-gay marriage." The ad, from the American Principles Fund, suggests that Cheney isn't sufficiently conservative on the latter issue. It singles out comments Cheney made on MSNBC in 2009 in opposition to a constitutional ban on gay marriage and in support of a State Department decision to extend benefits to same-sex couples.