Nightly News | March 15, 2013
>>> now to another story getting attention today. the public discussion now under way about the future of the republican party playing out in a very public way today. as conservatives gathered for the big cpac conference in washington a prominent republican senator being considered as mitt romney 's vice presidential running mate made an announcement today that surprised his party, announcing his support for same-sex marriage. and mitt romney himself made news today reemerging on the national stage to a warm reception in the room. andrea mitt kchell is following it all from the d.c. newsroom. good evening.
>> reporter: good evening, brian. as thousands of conservative republicans gather outside washington the party's identity crisis is personified by rob portman 's change of heart on same-sex marriage.
>> wow, what a crowd.
>> reporter: on mitt romney 's short list for vice president rob portman voted against same-sex marriage in the house and senate. he said it was a matter of faith. now it's a matter of family. after his 21-year-old son will, a junior at yale, came out to his h parents two years ago.
>> i think this is something we should allow people to do -- to get married and have the joy and stability of marriage that i have had for over 26 years. i want all three of my kids to have it including my son who is gay.
>> reporter: will on a trip with his father and older brother tweeted, especially proud of my dad day. portman joins former vice president cheney who backed his daughter mary and her spouse. and 130 prominent republicans who signed a brief citing the supreme court challenge to proposition 8 which bans same sex marriage. while 51% of americans for the first time support same sex marriage in a nbc news wall street journal poll it is opposed by republicans by more than two to one.
>> senator marco rubio .
>> reporter: at the political action conference rising stars like marco rubio preached to the choir.
>> just because i believe states should have the right to define marriage in a traditional way doesn't make me a bigot.
>> reporter: and a mitt romney reemerged and apologized for losing.
>> it is up to us to learn from our mistakes, my mistakes and we take advantage of that learning to make sure we we take back the nation and put in place conservative principles.
>> reporter: republican critics say a group that courts donald trump and wayne la pierre .
>> you keep your advice. we'll keep your guns.
>> reporter: but shuts out new jersey's popular governor chris christie .
>> i wish them the best. let them have a great conference. the rest of it doesn't bother me a lot. i can't sweat the small stuff.
>> reporter: still hasn't learned how to win.
>> this has, over the last couple of years, become almost a " star wars " bar scene. when you have figures like donald trump as your headliners.
>> reporter: many of the critics say they won't start winning national elections until conservatives inside the room start reaching out to people outside the room including people like rob portman for whom gay marriage is now personal. brian?