A new Gallup poll released Sunday shows Pres. Barack Obama's approval rating has dropped below 40 percent for the first time ever, FoxNews.com reports.

The poll "says 39 percent of Americans approve of Obama's performance, while 54 percent disapprove. … A deeply unsettled political landscape, with voters in a fiercely anti-incumbent mood, is framing the 2012 presidential race 15 months before Americans decide whether to give Obama a second term or hand power to the Republicans. Trying to ride out what seems to be an unrelenting storm of economic anxiety, people in the United States increasingly are voicing disgust with most all of the men and women, Obama included, they sent to Washington to govern them."

Indeed, the rising dissatisfaction of voters with Obama played a role in luring Texas Gov. Rick Perry into a race for the Republican nomination that doesn't officially get underway until the Iowa caucuses on Feb. 6 and New Hampshire primary on Feb. 14. Perry, Mitt Romney and Jon Huntsman Jr. all spent parts of their weekend stumping for votes in the Granite State.

"Romney and Perry will be competing to face possibly the weakest incumbent since Jimmy Carter, with the world in turmoil and the economy adrift," Ross Douthat wrote in Sunday's New York Times. "Six months ago, it still seemed as if Republican primary voters might be choosing a sacrificial lamb to run against Barack Obama. Now it looks as if they might be choosing the next president."

Obama's initial response to sagging poll numbers is a three-day bus tour, the Los Angeles Times reported Monday morning.

"Obama Monday will embark on a three-state, five-town bus tour deep in the heart of the American Midwest, hoping to tell the public — and potential voters — some small-business success stories and highlight economic development in rural areas. He'll also be looking to rebut criticism that he's not focused on finding solutions to bolster the flat-lining economy."

Not surprisingly, Republicans are skeptical about the bus tour. CNN.com reports that a statement on the front page of Romney's website reads, "During his Magical Misery bus tour this week, it is unlikely President Obama will speak with unemployed Americans, to near-bankrupt business owners, or to families struggling to survive in this economy. He is more interested in campaigning in swing states than working to solve the economic crisis that is crushing the middle class."

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