Nine states that Barack Obama won but that John Kerry, the 2004 Democratic nominee, lost, show challenges for the president's reelection bid.

See story in The New York Times about the following states:

COLORADO
Approval Rating for Obama: 42 percent
Obama's 2008 margin of victory: 9.0 percentage points

FLORIDA
Approval Rating for Obama: 41 percent
Obama's 2008 margin of victory: 2.8 percentage points

INDIANA
Approval Rating for Obama: 38 percent
Obama's 2008 margin of victory: 1.0 percentage point

IOWA
Approval Rating for Obama: 42 percent
Obama's 2008 margin of victory: 9.5 percentage points

NEVADA
Approval Rating for Obama: 39 percent
Obama's 2008 margin of victory: 12.5 percentage points

NEW MEXICO
Approval Rating for Obama: 45 percent
Obama's 2008 margin of victory: 15.1 percentage points

NORTH CAROLINA
Approval Rating for Obama: 39 percent
Obama's 2008 margin of victory: 0.3 percentage points

OHIO
Approval Rating for Obama: 42 percent
Obama's 2008 margin of victory: 4.6 percentage points

VIRGINIA
Approval Rating for Obama: Not available
Obama's 2008 margin of victory: 6.3 percentage points