Gallup Daily: Obama Takes Lead Over McCain, 48% to 42%

PRINCETON, NJ -- Barack Obama is enjoying a modest bump in support following Hillary Clinton's exit from the presidential race. The latest Gallup Poll Daily tracking update finds Obama leading Republican John McCain, 48% to 42%, among registered voters nationwide.

Obama has consistently held a lead of five to seven percentage points each night since it was reported that Hillary Clinton intended to suspend her campaign. These represent Obama's strongest showing versus McCain to date in Gallup Poll Daily tracking of registered voters' presidential election preferences. For much of the time since Gallup began tracking general election preferences in mid-March, McCain and Obama have been in a statistical dead heat. (To view the complete trend since March 7, 2008, click here.)

Today's data are based on June 6-8 interviewing. Gallup had been reporting a five-day rolling average for the general election to this point, but now that the major party candidates are known Gallup will move to reporting a three-day rolling average. Obama would still hold a statistically significant lead (matching his best to date) in the five-day rolling average based on June 4-8 interviewing given his recent stronger performance.

Since Obama clinched the nomination, Gallup has also asked registered voters for their Obama-McCain preference if Clinton were Obama's vice presidential running mate. At this point, Clinton would seem to give a slight three-point boost to Obama's margin over McCain, with the Obama-Clinton ticket leading McCain by an average of 51% to 42% over the past three days.

There is not an overwhelming consensus among Democrats that Obama choose Clinton as his No. 2. In the latest Gallup Poll Daily tracking update (based on June 6-8 data), 53% of Democrats say Obama should pick his former nomination rival for vice president, while 36% say he should choose someone else. -- Jeff Jones

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 June 6-8, 2008. For results based on this sample of 2,389 registered voters, the maximum margin of sampling error is ±2 percentage points.

For results based on the 1,516 Democrats and Democratic leaning-independents interviewed June 6-8, the maximum margin of sampling error is ±3 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.