Hong Kong's pro-democracy protesters are at a crossroads -- as public support fades after nearly two months of mass sit-ins and gridlocked traffic, activists are split on whether to retreat or ramp up their campaign.

With little hope of fresh dialogue between protesters and government, the spectacle of a small faction smashing up a side entrance to Hong Kong's legislature on Wednesday left a sour taste in a city where criminal damage is extremely rare.

And a thwarted attempt by student leaders to fly to Beijing and take their demands for free elections to China's authorities did little to alter cooling public opinion.

"The majority are against it. What they are asking for is reasonable, but it's causing a hindrance (to traffic)," said a 65-year-old gardener who gave his surname as Mo, waving a sprinkler as he tended to plants in public gardens around the main Admiralty protest site.

"There are many other ways to do it," he said. "People have to make a living. I don't know that much, but many people agree with me," he added.

Demonstrators are demanding free elections for the city's next leader, but Beijing insists that candidates for the 2017 leadership vote must be vetted by a loyalist committee.

Sit-ins and rallies at key intersections have brought traffic to a standstill and diverted buses and taxis, leaving commuters and local businesses irate.

In a reflection of residents' growing frustration, the protests have suffered a steady drop in popular backing -- 83 per cent of respondents in a Hong Kong University poll of 513 people said this week they want the occupation to end, and just over 60 percent declared the government should clear the protest areas.

A similar study by the Chinese University of Hong Kong conducted a month ago suggested just 35.5 percent of 802 respondents were opposed to the occupation.

- 'Out of proportion' -

Since late September, a tent city has sprung up around the city government's headquarters, sprawling across a main thoroughfare in the downtown Admiralty district, which now boasts an outdoor gym, study area, medical tent and art installations.

Nightly rallies by charismatic protest leaders calling for fully free leadership elections in the semi-autonomous Chinese territory were initially attended by tens of thousands, and two more sites quickly appeared in densely packed shopping districts.

But some high-profile figures from within the movement argue the occupation has run its course and would better serve the ideals of greater democracy -- a principle that still enjoys broad public support -- by changing tack.

"If the occupy movement has induced negative sentiment among residents, it could mean the scale of disturbance may have gone out of proportion, making it necessary to shift to other means of disobedience," Chan Kin-Man, one of the founding members of the Occupy Central group, wrote in an editorial this week.

His sentiment was shared by heavyweight backer Jimmy Lai, a media magnate whose popular tabloids have been broadly supportive of the movement, in an interview with an Australian newspaper.

Hong Kong authorities are acutely aware of the slide in public support, reviving failed attempts to clear the sites after a court granted an order to remove obstructions this week, beginning with some barricades in Admiralty.

Similar action is expected imminently in Mong Kok, a working-class district and focal point for clashes between police, demonstrators and anti-protest groups.

- 'No retreat for the sake of it' -

The masked activists who damaged the legislature included two members of the more radical "Civic Passion" group, whose leader told the South China Morning Post he was sympathetic to their "frustration", while stopping short of endorsing their actions after the pair were arrested.

Student leaders seemed initially mystified by the incident, suggesting a lack of co-ordination with more militant protesters, and only condemned it hours later by saying those involved had the responsibility to act in the interest of the wider public.

The incident has also buoyed Beijing's supporters in Hong Kong, as China considers the protests illegal and has attempted to paint the protesters as violent criminals.

Whatever happens next, some protesters are determined to maintain the occupation's status quo. Student protester Louis Tong has lived at the main protest site since its early days, and has no intention of leaving.

"We should not retreat for the sake of retreating. Democracy is not just a mechanism. It should be a state of mind," he said, as two protesters on stationary bikes behind him exercised on what used to be a nine-lane highway.

"We need to bring the message to the public."