The nationwide competition is asking voters to pick their favorite landmarks in Russia, either online or by text message.
The competition's website describes its goal as "highlighting Russia's diversity and originality" and thereby boosting tourism in the country.
After the contest ends on September 29, authorities plan to build small-scale replicas of the top 10 landmarks and place them in a park outside Moscow that they hope will draw millions of visitors every year.
The contest -- organized by the Russian Geographical Society, which is chaired by Defense Minister Sergei Shoigu, and several Kremlin-friendly media outlets -- had generated limited public interest since its launch in March.
But since a mosque in Chechnya unexpectedly shot to the top of the list in mid-August, the competition has drawn intense scrutiny.
Ramzan Kadyrov, Chechnya's iron-fisted leader, says Chechens have been voting en masse for the main mosque in Grozny, built after Chechnya's two separatist wars with Moscow and named after his father, Akhmed Kadyrov.
According to his spokesman, Elvi Kerimov, the mosque's success in the competition simply reflects its popularity in Chechnya and beyond.
"It's due to people's spirituality, to their devoutness. For them, the mosque is a symbol of faith, of kindness, of dignity," Kerimov says. "People don't cast their vote only in Chechnya. We receive messages and photographs from people who vote from other regions of Russia. It's good to see that the mosque unites our society."
'Heart Of Chechnya'
Also known as the "Heart of Chechnya," the Akhmed Kadyrov Mosque -- Europe's largest -- has already gathered nearly 37 million votes.
Critics, however, accuse authorities in the predominantly Muslim republic of distorting the results by waging an aggressive campaign to drum up votes.
Kadyrov himself has repeatedly urged all Chechens to back the mosque, saying its victory in the competition would be "a triumph of tolerance."
A number of Chechen officials and Muslim leaders have followed suit, including the speaker of Chechnya's parliament, Dukvakha Abdurakhmanov, and the deputy mayor of Grozny, Ismail Khusainov.
But few have been as vocal as Chechnya's deputy mufti, Magomed Khiytanayev, who pledged earlier this month that all those who vote for the mosque "will be happy on judgment day."
Khiytanayev also said that the few rubles spent on every text message vote "amount to multiple acts of charity in the eyes of [God]."
The campaign, however, has exasperated many Chechens.
Larissa, a resident of a town in the northern Nadterechny district, says crowds of people are regularly bussed to rallies and concerts organized in Grozny to support the mosque's candidacy.
"They bring several singers and presenters. After each song, the presenters urge us to vote, to send [a text message]," Larissa says. "Then comes another song, after which they tell us again: 'Spare three rubles, send [a text message]!' They also tell us to vote 'for Allah's sake.' And everyone votes."
'I'm So Tired Of This'
Khava, a school director in the Nadterechny district, says teachers are often threatened with dismissal if they fail to attend such rallies and cast their vote.
"People don't want to go there. But it doesn't matter whether we want to go or not, they can fire us," Khava says. "I'm so tired of this."
Grozny's feverish push to win the competition has angered Russian nationalists, who have called on all voters to elect the Kremlin complex in the city of Kolomna in a bid to dethrone the "Heart of Chechnya."
Flash mobs and rallies, during which participants hold specially printed flags, have been staged to get people behind the Kolomna Kremlin.
The imposing 16th century structure, southeast of Moscow, has enjoyed a surge of support since this initiative began, As of August 30, it had overtaken the mosque at the top of the rankings, with a lead of roughly 400,000 votes.
NOTE: This article has been amended since publication to reflect changes in the rankings. You can find the latest poll standings here.