Rick Santorum Announces He's Running For President In 2016

Former Sen. Rick Santorum (R-Pa.) announced Wednesday that he is running for president in 2016.

Santorum made the announcement in Butler County, Pennsylvania, where he grew up.

"Today is the day we are gonna begin to fight back," Santorum said in his remarks.

It's the second presidential campaign for Santorum, who also sought the GOP nomination in 2012 . He won 11 primaries during that race.

Santorum, who is strongly opposed to same-sex marriage, will bring a staunchly conservative voice to the race at a time when some Republicans are asking the party to de-emphasize social issues to appeal to a wider electorate.

Santorum served in the House from 1991 to 1995 and in the Senate from 1995 until 2007. In the House, he was a member of a group of high-profile freshmen called the "gang of seven," which antagonized members of both parties. Santorum was elected chairman of the Republican conference in the Senate in 2000, the No. 3 position in the body, despite having a reputation for an aggressive style that former Sen. Robert Byrd (D-W.Va.) said was more appropriate for ''an alehouse or beer tavern.''

Earlier this year, Santorum and his wife released a book detailing his daughter's struggle with Trisomy 18, a rare genetic disorder that is fatal to many children who are born with it. Santorum partly attributed his decision to drop out of the 2012 race to his daughter's condition taking a turn for the worse.

Santorum joins a crowded field of Republicans seeking their party's nomination. According to HuffPost Pollster, which aggregates publicly available polling data, Santorum has the backing of just 1.5 percent of Republican voters.

This post has been updated to include comments from Santorum's announcement.