In a quiet moment, when the last vote has been recounted in the battle for Melbourne and the nation's political gaze has moved on, Greens officials will have one question for their most trusted supporters -- where the bloody hell were you?

Across the urban expanse of the Melbourne electorate, the Greens' vote cut deeper into Labor territory, winning new support in places such as Kensington and the Docklands, North Melbourne and the CBD.

Yet in the greenest patch of the seat the vote fell curiously flat, with low turnout and apathy conspiring against the party's lower house ambitions.

Since 2002, when the Greens registered their first candidate in a state election, the Lee Street primary school in Carlton North has delivered the strongest Greens vote in Victoria at every state and federal poll.

For the first time, support at that booth inched backwards this by-election, as voters who previously rode the Greens wave failed to rally to the cause.

The Greens still beat Labor comfortably at the three Carlton voting booths, just north of the CBD. Yet at all three booths their share of the vote slipped from the highs of the 2010 state election.

After Saturday night's count, a total of 111 voters who plumped for the Greens in Carlton two years ago were unaccounted for.

Some were overseas, some were at the football and some voted for candidates other than Cathy Oke. Whatever the reason, they weren't there for their party in its time of need. Where Oke secured 41.7 per cent of the vote at the Errol Street booth in North Melbourne, near her parent's house, she got a poor 38.4 per cent of the vote at Carlton Central, down from 39.8 per cent two years ago.

At Carlton's Rathdowne Village, where locals take their Sunday coffee beneath the Victorian-era awnings of cafes, bookstores and french bakeries, various reasons were given to explain the polling plateau.

Bonnie Karklins, 26, a hospitality manager who has voted Greens since she was old enough to enrol, said the Greens were becoming a big party and with that came different pressures. "I like it that they are getting bigger but there is that worry that as they get bigger they will promise to do things that they actually can't," she said.

Tim Mooney, 27, an IT worker, said the Greens had become his second or third preference. On Saturday, he voted for the Sex Party, which directed its preferences to Labor. "I am more into anti-censorship and free speech," he said. "The Greens, it seems like they pretend to care more about a lot of stuff than they actually do."

Seated outside an elegant cafe with her family on a sunny winter's day, Ellenie Georgiou said she had not voted. If she did, it would probably have been another donkey to add to the 2426 informal votes lodged. Ms Georgiou, 39, works in media sales and describes herself as a Liberal voter, though one disappointed with the Baillieu government. The Liberals did not field a candidate on Saturday. Georgiou went to the football.

Victorian Greens electoral analyst Stephen Luntz said fewer voters turned out across the three Carlton booths compared to 2010, which was in line with the rest of the electorate.

He said part of this could be attributed to the transitory nature of inner Melbourne, home to a high proportion of students and rental properties.

While the number of people on the Melbourne electoral roll has changed little since the 2010 state poll, this does not take into account voters who have moved and are still enrolled and voters who have moved in but have not yet updated their electoral details.

Mr Luntz doubted the Greens' vote had peaked in Carlton, but could not rule it out.

"There are certainly plenty of people who think that. I would agree there is some evidence for that theory, but I don't think you can call it at this point."

Source: The Australian