Hoping to overcome President Barack Obama's recent endorsement of his opponent, U.S. Rep. Ahn "Joseph" Cao is accusing Obama of failing to properly check out the people he's endorsing.

Cao is a Vietnamese-American Republican in a mostly black, Democratic district where President Barack Obama is popular. Cao's statment notes past ethics investigatons of his main opponent, Democratic state Rep. Cedric Richmond, plus the six-month suspension of Richmond's law license in 2008 for falsely documenting his residency in a city council race.

Obama endorsed Richmond last month and was featured in a Richmond television ad that aired Sunday in the New Orleans area. Cao won the seat in the New Orleans-based district two years ago over scandal-plagued incumbent William Jefferson.