PRINCETON, NJ -- It's official: Barack Obama has received no bounce in voter support out of his selection of Sen. Joe Biden to be his vice presidential running mate.
Gallup Poll Daily tracking from Aug. 23-25, the first three-day period falling entirely after Obama's Saturday morning vice presidential announcement, shows 46% of national registered voters backing John McCain and 44% supporting Obama, not appreciably different from the previous week's standing for both candidates. This is the first time since Obama clinched the nomination in early June, though, that McCain has held any kind of advantage over Obama in Gallup Poll Daily tracking.
The race for president has been virtually tied since mid-August. In this period, Obama's support from national registered voters has consistently ranged from 44% to 46%. The 46% currently supporting McCain is technically his best showing since late May/early June, but is not a statistically significant improvement over his recent range from 43% to 45%. (To view the complete trend since March 7, 2008, click here.)
An analysis of historical election poll trends by Gallup Poll Managing Editor Jeff Jones shows that recent presidential campaigns have enjoyed a small (though short-lived) bounce from the running mate announcement. This includes a four percentage point bounce for John Kerry in 2004 after selecting John Edwards, a 5-point bounce for Al Gore in 2000 with his announcement of Joe Lieberman, and a 3-point bounce for George W. Bush in 2000 upon choosing Dick Cheney. Bob Dole received an extraordinary 9-point bounce in 1996 after bringing Jack Kemp onto his ticket.
All of these bounces occurred before the respective party's convention began, and in most cases the candidates received an additional boost in the polls upon completion of the convention. Thus, any increase in Obama's support in the coming days would seem to be more the result of the star-studded and well publicized Democratic national convention than the apparently lackluster Biden selection.
The official Gallup records will show that support for Obama declined by two percentage points in Gallup Poll Daily tracking (from 46% to 44%) conducted immediately before and after the Aug. 23 Biden announcement. (Because the announcement was made at 3 a.m. on Saturday, Aug. 23, all Gallup interviewing conducted that day can be considered post announcement.)
Today's Gallup Poll Daily tracking result includes interviewing on the first night of the Democratic National Convention (Aug. 25). However, much of this interviewing, particularly in the East and Midwest, was conducted before the prime time convention speeches by Sen. Ted Kennedy and Michelle Obama. The Gallup Poll Daily tracking results reported tomorrow may start to indicate whether voters are impressed enough by what they are seeing at the convention to give Obama the bounce that typically occurs as a result of a party's convention. -- Lydia Saad
Click here to see how the race currently breaks down by demographic subgroup.
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. 23-25, 2008. For results based on this sample of 2,684 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.
To provide feedback or suggestions about how to improve Gallup.com, please e-mail feedback@gallup.com.
