Some 940,000 Hong Kongers have begun casting their votes for the legislator of their choice in an election that will shed some light on how much support a radical movement that advocates the use of violence has.
Residents of the New Territories East district - in the north-eastern part of Hong Kong - are electing their Legislative Council representative on Sunday (Feb 28) in a by-election.
Polls opened at 7.30am and will close at 10.30pm.
But its significance goes beyond that of a legislative poll in one constituency.
Among the seven candidates is 24-year-old philosophy undergraduate Edward Leung, spokesman for Hong Kong Indigenous - the radical group alleged to have orchestrated the violent clashes between police and protesters in Mongkok during Chinese New Year early this month.
Mr Leung was arrested for rioting and is currently out on bail.
How much support he gains on Sunday will indicate the extent to which mainstream society buys his group's argument that conventional methods to "safeguard" Hong Kong's identity and democratic values from Beijing have failed over the past decades, and that street violence should now be deployed.
Such thinking, while still on the fringe, appeared to have gained ground in recent times, especially among the young.
In a panel discussion this week, he argued for the need to reform Hong Kong's electoral system, including the removal of functional constituencies which generally represent pro-Beijing and vested interests.
"They do not represent the people... we have to use whatever means to stop it."
While Mr Leung - currently placed third in polls - is unlikely to ultimately win, the number of votes he gets will influence the results.
The two front runners running neck and neck are from Hong Kong's two broad political camps: Mr Alvin Yeung, 34, a barrister from the Civic Party, a relatively moderate pro-democracy party, and Mr Holden Chow, 36, a solicitor from the pro-establishment Democratic Alliance for the Betterment and Progress of Hong Kong.
The more support Mr Leung gets, the more he will chip away at Mr Yeung's base of pro-democracy voters.
This means that Mr Chow could end up the eventual winner.
This in turn will shape the broader political landscape.
It will neatly flip the razor-thin majority that the pan-democrats now hold in the LegCo's 35 geographical constituencies, and will give voting power to the pro-establishment when it comes to legislator-proposed bills.
Mr Chow had already promised that if elected, he will push for changes to LegCo rules that will ban filibustering - a tactic regularly used by pro-democracy legislators to block government-proposed policies.