(Undated) -- The law known as Obamacare will play a big role in this year's congressional elections and it could be the villain for Democrats. A "USA TODAY"/Pew Research Center Poll released this morning reports more than 80 percent of registered voters say a candidate's position on the Affordable Care Act will be an important factor in how they vote. And, by a 2-1 margin, people who say the issue is important don't like the law. That could have them leaning toward the GOP. Not one Republican voted for the law when Congress passed it four years ago.