Jackson has a long history with one of Obama's chief rivals, Sen. Hillary Rodham Clinton and her husband former President Clinton. He counseled the two when the president's affair with former White House intern Monica Lewinsky became public.
But Jackson said his history with the Clintons doesn't complicate his decision to back his home state senator, calling Obama Illinois' "favorite son."
"It's not awkward at all," he said, adding, "I don't owe a debt to any of them."
How much does Al Sharpton owe?
— Jesse Jackson Rainbow Coalition