Well, duh. We knew that.
"These are essentially conservative Republicans who are very ticked-off people," said Republican pollster Bill McInturff, who conducted the survey with Democratic pollster Peter Hart.
If the Republicans win control of the House or Senate this fall, Mr. McInturff added, the survey shows "enormous amounts about how limited the interest is going to be in those new majorities to try to seek negotiation with the president or the Democratic leadership."
The poll found that tea-party supporters make up one-third of the voters most likely to cast ballots in November's midterm elections. This showed the movement "isn't a small little segment, but it is a huge part of what's driving 2010," Mr. Hart said.
The survey also found growing energy among some core Democratic voting blocs, such as African-Americans and Hispanics—a tightening that is common as an election draws closer, according to pollsters.
The GOP now holds a three-point edge, 46% to 43%, when likely voters are asked which party they would prefer to control Congress. That is down from a nine-point Republican lead a month ago.