A majority of U.S. voters in important swing states say they are not better off than they were four years ago, according to poll results released on Monday, as Republican and Democratic parties are gearing up for their national conventions to nominate their presidential candidates.

According to a USA Today/Gallup Swing States poll, 56 percent of respondents in swing states said they were not better off than PresidentBarack Obamafirst took office. That included 50 percent of independent voters in the swing states, in addition to 36 percent of Democrats and 84 percent of Republicans saying they are not better off. About 40 percent of voters in swing states say they are better off.

The question is relevant in 2012 as Obama seeks a second term as president with the economy still struggling to recover from the 2008-2009 recession. The fact that the majority of voters in the crucial states that will decide the election believe they are not better off is a challenge for the Obama campaign.

However, it is possible that voters may cut Obama some slack on the economy, given that he took office during one of the worst economic downturns in U.S. history. The poll finds that voters do not widely blame Obama for their circumstances. Twenty percent of swing-state voters say they are not better off and blame Obama alone. Another 15 percent are not better off and blame Obama but also blame former president George W. Bush. And 21 percent do not blame Obama, including 7 percent who believe Bush alone is responsible.

In a sign swing-state voters haven't made up their minds about who they'll elect in the coming election, the poll finds they are not convinced they would be better off in four years underMitt Romney, Obama's Republican challenger. Forty four percent predict they would be better off four years from now if Romney wins and 49 percent say they would not be better off. Those figures are roughly the same when voters are asked to predict their situation in four years if Obama is reelected -- 42 percent say they would be better off and 52 percent say they would not be.

The poll was conducted Aug. 6-13 with a sample of 970 registered voters in swing states including Colorado, Florida, Iowa, Michigan, Nevada, New Hampshire, New Mexico, North Carolina, Ohio, Pennsylvania, Virginia, and Wisconsin. It has a sampling error of 4 percentage points.