Republican Scott Brown's victory in Massachusetts has forced congressional Democrats and the White House to assess their agenda going forward. The historic win in the solidly Democratic state has put the brakes on President Obama's and congressional Democrats' key legislative initiatives: health care reform, climate change and a second stimulus. Obama's agenda already was in trouble before the GOP victory in Massachusetts, said Larry Sabato, director of the University of Virginia's Center for Politics. "The Massachusetts special election crystallized just how much trouble Obama's legislative agenda was in," he said. "The sense I got was that members prior to Christmas didn't really think that most of Obama's agenda was going to pass anyway after health care." The reason, Sabato said, that in the coming mid-term elections, conservative Democratic members may feel they'd already given Obama enough support. CNN Political Editor Mark Preston notes that heading into 2010, Obama already faced a tough task of convincing congressional Democrats to rubber stamp his agenda. But the loss in Massachusetts makes it even harder for him to get other bills passed.