Elizabeth Warren’s bid for US Senate made her a liberal icon. But in her victory speech, she showed a welcome recognition that she needs to be more than that. “The message you sent was clear,” Warren said to supporters of Republican Scott Brown, who touted his independence on key votes. “We need leaders in Washington who are willing to break the partisan gridlock and to work together regardless of party.” While that means setting a respectful tone, it should also mean finding policy areas where bipartisan agreement is possible. One place to start is on reforming Fannie Mae and Freddie Mac — the bailed-out behemoths that dominate the nation’s mortgage market. Warren’s expertise should prove helpful, and could bring along Democrats who’ve been leery of GOP criticisms of the firms. It’s a way to show voters of all parties that tough problems can and should be solved.