As House Democratic leaders and liberal groups ratchet up the pressure on vulnerable Democrats to support the health care bill this week, the U.S. Chamber of Commerce is warning 10 of them of risks at the ballot box if they vote "aye." The chamber commissioned polls in 10 battleground districts held by Democrats. In all 10, voters told the group's pollster they overwhelmingly oppose the health care legislation and would be more likely to vote to re-elect their Member if they vote "no" on the health bill. The targeted 10 were Reps. Gabrielle Giffords (Ariz.), Betsy Markey (Colo.), Allen Boyd (Fla.), Dina Titus (Nev.), Michael Arcuri (N.Y.), Larry Kissell (N.C.), Steve Driehaus (Ohio), Jason Altmire (Pa.), Chet Edwards (Texas) and Glenn Nye (Va.). Of the 10, voters in Edwards' district showed the strongest opposition to the bill — 60 percent opposed and 30 percent supported it. At the other end was Nye's district, where 50 percent were opposed to the bill and 39 percent supported it. All the surveys were conducted March 8-11 by Ayres, McHenry & Associates. Each survey included about 400 registered voters in each district and had a 4.9-point margin of error. "There should be absolutely no question in anyone's mind how Americans view this health care bill," said Bruce Josten, the chamber's executive vice president of government affairs. "This legislation is among the most unpopular proposals in recent memory and Members of Congress would be well advised to listen to their constituents' concerns." The warning from the Chamber comes as liberal groups drop some $11 million on national ad campaigns that target Democrats who are wavering on whether to support the health care bill ahead of the vote.