by Dan Balz - Sept. 1, 2010 12:00 AM
Washington Post
WASHINGTON - The Gallup organization dropped a bomb on the political world this week. In shorthand, the pollsters said Monday that if the midterm elections were held now, Republicans would take control of the House, probably by a comfortable margin.
On Tuesday, James Campbell, a professor of political science at the University of Buffalo, weighed in with a prediction based on his modeling of the political climate. He said that Republicans are poised to gain 51 or 52 
Election Day is still two months away, but the twin findings added to the fear among Democrats that their House majority is in jeopardy and possibly their Senate majority as well.
For decades, Gallup has asked voters the following question: "If the
This week's survey produced the largest lead for Republicans in the history of asking that question: a margin of 51 to 41 percent. The Gallup survey, based on interviews with registered voters, was taken Aug. 23-29 and has a margin of sampling error of plus or minus 4 percentage points.
Ninety-six percent of Republicans said they would vote for the GOP candidate, while 88 percent of Democrats said they would support the Democrat. Independents, who helped power Democratic victories in 2006 and 2008, split 48 to 31 percent for Republicans.
This measurement, known as the generic ballot question, has sometimes been considered an imperfect or misleading indicator of House election results. However, Frank Newport, editor in chief of the Gallup poll, said that Gallup's final survey of likely voters before Election Day has been an accurate predictor of the two parties' share of the national vote in House elections. The national vote, in turn, he added, is an excellent predictor of seats won or lost.
Four years ago, when Democrats won control of the House, the final Gallup survey of likely voters gave Democrats an advantage of 7 percentage points over Republicans. Their actual share of the national two-party vote was 8 points more.
In 1994, when Republicans won the House and Senate, Gallup showed the GOP with a 7-point advantage in its final survey, exactly the margin between the two parties on Election Day.
In both those elections, the Democrats' share of the two-party vote was almost identical to their share of House seats after the election. And in those elections - and all midterms between 1994 and 2006 - the number of seats won by the Democrats was within three of the number predicted by Gallup's models.
Gallup won't start measuring attitudes among likely voters until late September or early October.
There are some cautionary notes. Gallup's generic ballot measure has fluctuated between late August and early November in past midterm contests. Four years ago, Democrats were ahead by 6 points in August, by 19 points in October and by 8 points in the final survey. In 1994, the two parties were tied in August, October and early November, but the final survey showed the GOP with a clear advantage. So things can change.
