A new Gallup Poll shows only 18% of Americans are satisfied with the way things are going in the United States -- a potential danger sign for President Obama.

Gallup did point out that in some recent election years -- including 1992, 1996 and 2008 -- satisfaction has been relatively low. "Of these years, only in 1996 did satisfaction improve over the course of the year, to 39%, a level high enough to help incumbent Bill Clinton win re-election," Gallup said.

"Satisfaction is one of several key measures, along with presidential approval and economic confidence, that help predict election outcomes," Gallup reported. "When Americans are largely dissatisfied with the way things are going in the country, incumbents and incumbent political parties are vulnerable to defeat."