Do Presidential Candidates Get a Bump from National Conventions?

The Republican and Democratic national conventions are set to begin. So how much will the party conventions, often described as mere lavish soirées for the political elite, actually help Mitt Romney and Barack Obama in the polls?

About 6 percentage points.

See also:

• Democratic National Convention Speakers
• Republican National Convention Speakers
• When Are Vice Presidential Candidates Chosen?

Presidential candidates have seen, on average, a 6-point bump in the polls immediately following their party's national conventions since 1964, according to a new analysis from the Gallup organization. The median bump is 5 percentage points.

The 1992 Democratic presidential nominee, Bill Clinton, holds the record for the largest bounce following his party's national convention. His poll numbers show up 16 percentage points.

"Clinton's 16-point bounce came after he was running third behind Republican George H.W. Bush and independent Ross Perot in polls in the spring and early summer of 1992," Gallup researchers wrote. "Perot dropped out of the race during the Democratic convention, at which Clinton and the Democrats successfully got voters to focus on the poor state of the economy and to blame Bush for it."

The only candidates to not experience a post-convention bounce were Democrats George McGovern in 1972 and John Kerry in 2004.

So what about Romney and Obama? They can expect to see an average bounce. Maybe.

"There are parallels between the 2012 and 2004 contests that suggest voter preferences may not be affected much by this year's conventions, as was the case in 2004," Gallup analysts wrote. "Both the 2012 and 2004 elections involved incumbent presidents seeking re-election with below-average approval ratings. The approval ratings in the high 40% range for both Bush and Obama may be a function of highly polarized views of them by party, generally a greater partisan divide than for other presidents.

"Also, in both elections a high percentage of Americans were paying attention to the campaigns before the conventions. In other words, if voters are already tuned in to the election and already have made up their minds on whether Obama deserves a second term, neither he nor Romney may see his support change much after the convention."

[2008 Democratic National Convention / Getty Images News]

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