But this only earned them 25 legislative seats due to the vagaries of Hong Kong's political system.
Despite the waning popularity of the current government, the pan-democrats have not been able to take advantage of the dissatisfaction, with polls suggesting their number of seats could fall.
In addition to the retirement of Martin Lee and Anson Chan, widely viewed as pro-democracy politicians, several other senior politicians could be relegated to political obscurity.
Two of the most senior politicans - Emily Lau, a former journalist and outspoken government critic and activist "Long Hair" Leung Kwok-hung - could lose their seats, a Hong Kong University poll showed.
"Hong Kong will not remain fair, open and democratic unless we are willing to fight. I am willing to fight and I ask you now for the greatest privilege of all: to fight for you," Leung said in an advert in the Sunday Morning Post.
Only 30 of the 60 legislative seats were being chosen by the city's 3.37 million registered voters.
The remaining 30 "functional constituencies" represent various business and industry interests chosen by select electorates.
Polls close at 14:30 GMT and results are expected to be in by Monday.
Although the election was promoted under the slogan, "Shape our future, cast your vote," the legislature has very limited power.
If the pan-democrats slip below 21 seats they will lose the ability to veto government legislation, which they successfully used in 2005 to block controversial constitutional reforms.
Hong Kong was promised universal suffrage for both its legislature and chief executive when colonial power Britain handed back the territory to China in 1997, but no specific timetable was set.
While the city's chief executive Donald Tsang - who was elected by a small group of mainly pro-China figures last year - is slipping in the polls after a number of blunders, the pro-Beijing parties appear in good health.
The Democratic Alliance for the Betterment and Progress of Hong Kong (DAB) has grassroots organisation and could also get a bump from the city's growing patriotism, reinforced by a recent visit by China's Olympic gold medallists.
It may also benefit from Beijing's announcement late last year that universal suffrage could be introduced here from 2017, neutering the democrats' key election asset.
But Michael DeGolyer, a politics professor at Hong Kong Baptist University, said his pre-election poll showed growing patriotism will not necessarily translate into more pro-Beijing votes.
"People are starting to treat their votes in the same way they deal with their investments," DeGolyer said.
"I do not know what the 'China factor' is. If the definition is 'support your country, vote for the DAB,' that is not the case anymore," he added.