Jimmy Carter, the oldest living former US president and the only one to have reached the age of 100, cast his vote for president on Wednesday in his highly contested home state of Georgia. The ballot was dropped in a mailbox at the courthouse in the city of Americus, several US media reported, citing the Carter Center. The former president told his family that he had more interest in voting for Vice President Kamala Harris, the Democratic nominee, than in his 100th birthday, according the the Atlanta Journal-Constitution. Carter, who is in poor health, had said he had a last wish and that was …