PRINCETON, NJ -- Gallup Poll Daily tracking from Aug. 30 through Sept. 1, finds Barack Obama leading the race for president with his highest share of support to date. Fully half of national registered voters now favor Obama for president, while 42% back John McCain.

Prior to now, no more than 49% of registered voters supported Obama for president in Gallup Poll Daily tracking. Still, Obama's eight percentage point lead over McCain in the new poll falls one point shy of the lead he attained in late July after returning from a well-publicized trip to Europe and parts of the Middle East. At that time, Obama led by nine points, 49% to 40%.

McCain's 42% support is well below his 48% top support level, recorded in late April/early May. It is just slightly better than the 40% he received at several points in July, and the 41% favoring him just last week while the Democratic National Convention was underway. (To view the complete trend since March 7, 2008, click here.)

At 8%, the percentage of undecided voters is slightly lower than the 9% to 11% figures seen for most of August, and this is the lowest this figure has been since early June. This, in part, reflects movement of voters toward Obama over the course of the Democratic National Convention, a lead which has been sustained in subsequent days.

The field period for today's results includes Monday (Labor Day), when the scaled down Republican National Convention received limited media attention while most news coverage either focused on the hurricane hitting parts of the Gulf Coast or Monday's surprise announcement that the 17-year-old daughter of the soon to be Republican vice presidential candidate, Sarah Palin, is pregnant. The Republicans hope to start up a more traditional convention schedule today in St. Paul, with the goal of capturing the same kind of media and public attention the Democrats did last week in Denver. -- Lydia Saad

Survey Methods

For the Gallup Poll Daily tracking survey, Gallup is interviewing no fewer than 1,000 U.S. adults nationwide each day during 2008.

The general-election results are based on combined data from Aug. 30-Sept. 1, 2008. For results based on this sample of 2,772 registered voters, the maximum margin of sampling error is ±2 percentage points.

Interviews are conducted with respondents on land-line telephones (for respondents with a land-line telephone) and cellular phones (for respondents who are cell-phone only).

In addition to sampling error, question wording and practical difficulties in conducting surveys can introduce error or bias into the findings of public opinion polls.

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