That’s not quite what Gallup explicitly says in its analysis, but it’s a rather inevitable conclusion when one sees the graphic presentation of the results.  Barack Obama lost eleven points in his approval ratings on a state-by-state basis in 2010, and now the floor has Obama in danger of losing the next election.  Bear in mind when looking at the legend that the “average” approval rating for Obama was 47% — and that Obama had a 50% or better rating only in the dark-green states:

Obama’s overall average approval rating in 2010 was 47%, down 11 percentage points from the 58% he recorded in his first calendar year in office. For purposes of this state-by-state analysis, Obama’s average is calculated for the calendar year, and is therefore slightly different than the yearly average calculated beginning with his inauguration on January 20, 2009.

Broadly speaking, residents of 20 states gave Obama an approval rating within three percentage points of his national average (between 43.8% and 49.8%). Twelve states plus the District of Columbia had average approval ratings above that range, and in 18 states, approval fell below it.

The graphic is striking.  Obama only gets majority approval for his performance on the West Coast and the Northeast — and not even all of those areas.  He holds his home state of Illinois and his birth state of Hawaii, both unsurprisingly, but between the coasts there exists a vast land of either indifference or outright disapproval.  Traditional Democratic states like Wisconsin, Michigan, and Pennsylvania are wavering.  The entire interior West has become outright hostile.  More than half of the states have shown a double-digit decline in approval for Obama.

Presidents can win re-election with overall approval ratings below 50%, but that usually requires either a credible third-party challenge or an extraordinarily poor challenger.  The economy would have to significantly improve to move these numbers in the direction where Obama can feel safe, and that seems unlikely to happen while Obama continues to press for regulatory adventurism.

Obama has a year at best to turn this around.  He won the 2008 election at the peak of Bush fatigue by seven points nationwide.  Continuing erosion in his standing puts the White House within the grasp of the GOP, especially if they nominate a credible candidate who can attract a “big tent” of those discontented with Obama.