As the Supreme Court considers the constitutionality of same-sex marriage this week, politicians have also been questioning their own stances on the issue. Just a few weeks ago, dozens of Republicans signed an amicus brief to the Court in the Proposition 8 case saying they supported a constitutional right to same-sex marriage. Among those Republicans are names like Jon Huntsman and Meg Whitman. A few days later, Ohio Senator Rob Portman joined that chorus after his own son came out as gay. So what's the basic for the conservative case for gay marriage? Jeff Cook-McCormac, senior advisor for American Unity PAC,  a super PAC that supports pro-gay marriage Republican candidates, explains. Our Washington correspondent, Todd Zwillich, is filling in as host all this week. Follow Todd on Twitter for the latest from Capitol Hill. Follow Todd for the latest from Washington //