If a panic button existed in the offices of vulnerable Democrats in Congress right now, they might be pressing it so often it wouldn’t have time to reset. A new CNN poll this week found that support for Obamacare is down to an all-time low of 35 percent. That helps explain the dramatic partisan reversal in another question CNN asked — about which party respondents would vote for in their congressional district. Two months ago, Democrats had a 50–42 percent lead on that critical “generic ballot” question. Now, Republicans have taken a 49–44 lead.