What is the fine-grained topic of the following text: Tokyo: Japanese Prime Minister Shinzo Abe has a chance to stay in power through the 2020 Tokyo Olympics and become the country's longest-ruling leader after his party decided this week to allow its presidents to serve a third straight three-year term. Only return the topic.
Shinzo Abe's potential to become Japan's longest-serving leader due to a party decision allowing third term presidency