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AP Poll: 1/4 of Voters Defecting to Other Party

President Barack Obama's winning coalition from 2008 has crumbled and his core backers are dispirited. It's now Republicans who stand to benefit from an electorate that's again craving change.

Nearly two years after putting Obama in the White House, one-quarter of those who voted for the Democrat are defecting to the GOP or considering voting against the party in power this fall. Just half of them say they definitely will show up Nov. 2, according to an Associated Press-Knowledge Networks poll released two weeks before Obama's first midterm elections.

Yet in a reflection of broad dissatisfaction with politics, just as many people who backed Republican presidential nominee John McCain are either supporting Democrats now or still considering how to vote.

Still, McCain voters - to borrow Obama's campaign rallying cry - are far more "fired up, ready to go." Two-thirds say they are certain to vote next month.

It's a wide enthusiasm gap that's buoying Republicans, who are poised for big electoral gains, and worrying Democrats, who are seeking to hang onto majorities in Congress as well among governors. Obama's party hopes its superior get-out-the-vote operation, updated from his groundbreaking campaign, can overcome Republicans' energized supporters to mitigate expected losses across the board.

While no president can be expected to fully rally his supporters when he's not on the ballot, the survey illustrates the wide scope of Obama voters' disappointment with the president and his policies almost halfway through his first term - and two years before he's likely to seek their backing again.

If the election for U.S. House of Representatives were held today, would you vote for:

2008 Obama voters
The Democratic candidate/Lean Democratic (71/6)
The Republican candidate/Lean Republican (2/5)
Other, Don't Know, Refused (13)
Do Not Lean (3)

2008 McCain voters
The Democratic candidate/Lean Democratic (5/2)
The Republican candidate/Lean Republican (7/67)
Other, Don't Know, Refused (15)
Do Not Lean (5)

How the Poll was Conducted

The AP-Knowledge Networks Poll is a unique study to find out how the electorate's political views have changed since the 2008 election.

This study included 1,254 adults on Sept. 17 to Oct. 7 who were originally part of a random sample of Americans surveyed up to 11 times throughout the 2008 campaign by The Associated Press, Knowledge Networks and Yahoo News.

The extensive national survey was conducted by Knowledge Networks of Menlo Park, Calif., under the direction and supervision of The Associated Press' polling unit.

Interviews were conducted online. The original sample was drawn from a panel of respondents Knowledge Networks recruited via random sampling of landline telephone households with listed and unlisted numbers. The company provides Web access to panel recruits who don't already have it. With a probability basis and coverage of people who otherwise couldn't access the Internet, the Knowledge Networks online surveys are nationally representative.

Results were weighted, or adjusted, to reflect the adult population by demographic factors such as age, sex, region, race, and education.

No more than one time in 20 should chance variations in the sample cause results to vary more than plus or minus 4.4 percentage points from the answers that would have been obtained if all adults in the U.S. were surveyed. The longitudinal nature of the study could contribute to additional sources of error.

There are other, potentially greater, sources of variability in surveys, including the wording and order of the questions.

The questions and results for the poll are available here.
By AP National Political Writer Liz Sidoti

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