NAIROBI, Kenya — President Uhuru Kenyatta was declared on Monday the winner of Kenya’s presidential election — for the second time this year.

Mr. Kenyatta received nearly 7.5 million votes in the repeated vote, held last week, the national elections commission announced.

Mr. Kenyatta also won the first election, in August, by 1.4 million votes. But the opposition leader, Raila Odinga, challenged the results, and the Supreme Court nullified the election in September, citing irregularities.

Backers of Mr. Kenyatta interpreted both of his wins as broad national support for the president, but opposition supporters said they had twice been disenfranchised by a process that lacked credibility.