Mike Pence of Indiana heads the party's conservative faction in the House, known as the Republican Study Committee.

NPR: After the Election, New Races on Capitol Hill

Ms. Giffords is a supporter of gun rights and a conservative on some fiscal issues and a member of the Blue Dog Coalition, a faction of conservative House Democrats.

WSJ: Giffords Shows Encouraging Responses

The ultra-conservative Salafist Al Nour party has seen members split off to form their own faction.

CNN: STORY HIGHLIGHTS