"I feel proud. This is my last election but those who will come after me will find an independent institution," he said.
In his statement, Chebukati stressed that Kenyans had voted and he was duty bound to announce the results which reflected the will of the people.
After pronouncing Ruto as the winner, the IEBC Chairman said: "In accordance with the law and the Constitution, I Wafula Chebukati hereby declare William Samoei Ruto as being duly elected as the President of the Republic of Kenya." He then appended his signature to the certificate and handed it to the president-elect.
And this closed a chapter of the elections which had been characterised by a string of complaints, court cases and hiccups that saw some of the elections suspended due to ballot paper mix up.
Life as the chairman of IEBC has not been a bed of roses for Chebukati. Stained by the nullified 2017 presidential election, the IEBC boss had to deal with constant concerns of the four presidential candidates seeking to succeed President Uhuru Kenyatta.
The two leading contenders - Ruto and Raila Odinga - had raised concerns whether IEBC was prepared to handle the elections. So had civil society groups.
They had raised issues on credibility of the voters register and the results transmission technology. They were concerned that IEBC was doing things at the last minute.
The simulation of results transmission, which was delayed until the last minute, puts Chebukati and his commission in sharp focus.
Besides avoiding a repeat of 2017, the IEBC chair was hoping to banish the ghosts of 2007 post-election violence and to boost confidence of the voters.
Though the IEBC chair has said several times that IEBC maintains an "open-door policy," the commission, and Chebukati in particular, is no stranger to claims of stonewalling.
In a recent letter to IEBC chair, 10 civil society organisations, under the banner of Angaza Movement, asked him to offer "clear communication" on issues they had raised on election preparedness.
The media has also found the task of reaching Chebukati rather arduous, with phone calls and text messages about critical matters often going unanswered.
Marcus Ageng'a, the programmes coordinator at the Elections Observers Group (Elog), said IEBC, by keeping to itself, runs the risk of its story being told by politicians.
"We will seek to verify that they are ready and are hopeful that they will share information on their preparedness. We need to tell our people that the IEBC has their house in order. If we tell our people that they have their house in order then they will be confident that the elections will be free and fair," Prof Makau Mutua, Raila's campaign secretariat spokesperson, said in an interview.
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A lawyer, Chebukati was tasked with shepherding a new commission in 2017. His team came into office in January 2017 at the height of opposition's distrust in electoral agencies.
The previous Issack-led commission was hounded out of office by the opposition and civil society groups who accused it of bungling the 2013 presidential election.
The credibility of the commission was dented by the Chicken Gate scandal, a mega corruption scheme through which officials from the IEBC - then the Interim Independent Electoral Commission (IIEC) - earned kickbacks to influence tender awards to a British printing firm.
After four years of agitation, IIEC group agreed to resign but negotiated a hefty send-off package on their way out.
The late Samuel Kivuitu and the Electoral Commission of Kenya he chaired also left in the wake of the disputed 2007 elections, whose results he admitted to having been "cooked."
Observers say Chebukati had sufficient time to prepare for this year's contest, the perennial budgetary constraints notwithstanding.
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