Singapore, Sep 2 : Registering a landslide victory in Singapore's presidential election, Tamil-origin economist Tharman Shanmugaratnam said that his win was a vote of confidence in the city-state's future and vowed to build a 'future of optimism'. Tharman received a resounding mandate with a whopping 70.4 per cent votes in a three-way contest to elect the city-state's ninth President on Friday. 'I pledge and it will be my duty to use the roles and responsibilities of the president to advance this future of optimism and solidarity among Singaporeans. That is my pledge,' Tharman said in his first remarks to the media after his win. 'Once again, let me just say that I am truly humbled, and I will honour the trust that Singaporeans have placed in me and respect all Singaporeans for the views they have expressed, including those who did not vote for me,' Tharman said, as reported by The Straits Times. Thrman's rivals, Ng Kok Song and Tan Kin Lian, received 15.72 and 13.88 per cent of the vote, respectively. Congratulating Tharman for winning by a 'decisive margin', Prime Minister Lee Hsien Loong said the former senior minister will carry out his duties as president with distinction, having had a long and distinguished record of public service. 'He must exercise his custodial powers under the Constitution wisely, bringing to bear his experience and independent judgment,' Lee said in a statement, adding that internationally, the president must fly the country's flag high as Singapore's representative. It was for the third time that Singaporeans voted for their President since the elected presidency was introduced in 1991. The first such contested election was in 1993, followed by the second one in 2011. Before Tharman, Singapore has had two Tamil-origin presidents -- Sellapan Ramanathan who became the city-state's longest-serving president in 2009, and Chengara Veetil Devan Nair, who served from 1981 to 1985. Tharman joined politics in 2001 and has served in the public sector and ministerial positions with Singapore's ruling People's Action Party (PAP) for over two decades. He formally launched his presidential campaign in July with a pledge to evolve the country's culture to keep it a 'shining spot' in the world. Incumbent President Halimah Yacob's term will end on September 13. She is the country's eighth and first female president. /IANS