President Barack Obama launched the most comprehensive defense to date of his energy policies on Monday, pushing back against election-year attacks from Republicans who say they are to blame for high gas prices that are eroding his popularity with voters.

Heralding a report on energy security showing a big drop in U.S. oil imports, Obama acknowledged pain at the pump that analysts fear could lift gasoline to $5 a gallon in some parts of the country and pose a threat his Nov. 6 bid for re-election.