Barack Obama's grandmother, Madelyn Dunham, 86 has just died.

"It is with great sadness that we announce that our grandmother, Madelyn Dunham, has died peacefully after a battle with cancer," Obama said in a joint statement with his sister, Maya Soetoro-Ng.

"She was the cornerstone of our family, and a woman of extraordinary accomplishment, strength, and humility."

Dunham helped raised Barack or Barry as he was known then from the age of ten.

Obama took time off from the campaign to visit her on an emotional 22 hour trip to Hawaii two weeks ago.