Rep. Paul Ryan of Wisconsin said Tuesday night that he would run for House speaker — but only if his Republican colleagues meet several conditions. In the weeks since Speaker John Boehner of Ohio announced his retirement last month, Ryan — the Republicans' vice presidential nominee in 2012 — hadn't definitely said whether he wanted the job of herding the notoriously fractious Republican caucus, despite urging from colleagues across the political spectrum. That ended Tuesday night at a meeting of the House Republican Conference, where Ryan told fellow Republicans that he would run if the caucus unifies around a positive message of big ideas. "We need to move from an opposition party to a proposition party," Ryan told reporters. "If I can truly be a unifying figure, then I will gladly serve."