MOSCOW (Reuters) - A Kremlin-backed candidate is on track to be governor of a region on Russia’s Pacific coast, voting results showed on Sunday, after an election process in which the opposition had threatened the Kremlin’s usually tight grip on power.

Sunday’s vote in Primorsky region, which includes the port city of Vladivostok, was a re-run of a Sept. 16 election in which a Communist Party challenger claimed he was the rightful winner over the Kremlin’s nominee.

But that election was annulled by election officials, citing voting irregularities. Hundreds of people took to the streets at the time, saying the decision robbed the opposition of a rare election win.

Some political commentators said the September election showed fading public support for the Kremlin, the result of a weak economy and an unpopular proposal - since put on hold - to make people work for longer before they receive their state pension.

After the election re-run was announced, the Kremlin ditched its candidate from the September vote. Russian President Vladimir Putin installed as acting governor Oleg Kozhemyako, the governor of a nearby region with chiseled good looks and none of the political baggage of his predecessor.

Kozhemyako entered the election race, while the Communist challenger from the first round was disqualified from running on the grounds he failed to reach the threshold for winning endorsements from regional lawmakers.

With four fifths of the ballots counted on Sunday, Kozhemyako had a 60 percent share of the vote, according to the central election commission. His nearest rival, from the populist LDPR party, had 26 percent.

Election officials said there had been no reports of major violations, state television reported.

Kozhemyako’s win will restore the Kremlin’s familiar tight control over the region, but the circumstances in which the first election was annulled still rankle with some people.

“You’ve been insulted and humiliated,” Alexei Navalny, one of Putin’s most vocal opponents, said in a video message to voters in Primorsky region before Sunday’s vote.

“You voted and elected a person, after which the election was stolen, they spat in your face, and the person whom you elected was not even allowed to enter the election,” Navalny said.