President Barack Obama's approval rating has hit its highest point in two years — 60 percent — and more than half of Americans now say he deserves to be re-elected, according to an Associated Press-GfK poll taken after U.S. forces killed al-Qaida leader Osama bin Laden. In worrisome signs for Republicans, the president's standing improved not just on foreign policy but also on the economy, and independent Americans — a key voting bloc in the November 2012 presidential election — caused the overall uptick in support by sliding back to Obama after fleeing for much of the past two years.