"I am very sad to announce today the passing of my mother, Betty Anne
McCaskill. For some time, mom's health has not been good, and our family
takes comfort that she is now at rest," McCaskill said in the statement.
The senator is currently facing a challenge from Rep. Todd Akin (R-Mo.) for her seat. He issued a statement on Monday evening sending good wishes to her family.
"Lulli and I want to express our deepest condolences to Claire McCaskill and her family," he said. "Our thoughts and prayers are with the whole McCaskill family right now."
— Updated at 6:53 p.m.