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Input: TOKYO (Reuters) -  Japanese Prime Minister Shinzo Abeâs ruling bloc  scored a big win in Sundayâs election  bolstering  his  chance of becoming the nationâs longest-serving premier and re-energizing  his  push to revise the pacifist constitution.
âAnd as we saw in the U.K. ... a referendum could be tricky. So while  Abe  is likely to be prime minister for the time being  it is too early to say whether  he  can stay in power until 2021.â  Abe  declined to say if  he  would run for a third term.
 Abe  had said  he  needed a new mandate to tackle a "national crisis" from North Korea's missile and nuclear threats and a fast-aging population  and to approve  his  idea of diverting revenue from a planned sales tax hike to education and child care from public debt repayment [reut.rs/2yC0pma].
 He  called the poll amid confusion in the opposition camp and an uptick in  his  ratings  dented earlier in the year by scandals over suspected cronyism and a perception  he  had grown arrogant after nearly five years in office.

Abe to push reform of Japan's pacifist constitution after election win