Astana (Kazakhstan) (AFP) - Energy-rich Kazakhstan's incumbent strongman Nursultan Nazarbayev scored a crushing victory in Sunday's one-sided presidential ballot, taking 97.5 percent of the vote to win a fifth consecutive term, an exit poll showed.The exit poll carried out by the Institute for Democracy, a research company based in the authoritarian state, also showed Nazarbayev's closest competitor Turgun Syzdykov as scoring 1.8 percent of the ballot and third candidate Abelgazy Kusainov taking 0.63 percent.Kazakhstan's Central Election Commission (CEC) claimed a record voter turnout of 95.11 percent for the poll whose result was never in doubt.The CEC is expected to present preliminary results on Monday.The marginalised opposition did not field a candidate for the election and 74-year-old Nazarbayev stood against two figures widely seen as pro-government.Nazarbayev has ruled the vast Central Asian country since before the breakup of the USSR in 1991.