Icelanders voted on Saturday in an election that pits environmentalists against big industry backers, a contest experts believe may reshape the island nation's ruling coalition and potentially its economic future.
"It will be very close - neck and neck," said political science professor Olafur Hardarson at the University of Iceland. Initial results are expected after polls close at 2200 GMT although a final tally is unlikely until early on Sunday.
The election race has been dominated by a single issue - the tempo of big industry development in Iceland, which has a population of just 300,000.
The long-ruling Independence-Progressive Party coalition wants aluminium giants like Alcoa to keep building smelters powered by Iceland's geothermal and hydroelectric resources, a trend that has driven rapid economic growth in recent years.
Main opposition parties the Left Greens and Social Democrats want development halted until the environmental and economic impact of the latest projects becomes clear.
Prime Minister Geir Haarde, whose Independence Party led with 37 percent in the final opinion poll, expressed confidence after voting in Reykjavik. "I'm very optimistic," he told Reuters. "It's a beautiful day and I have no real reason to be worried or concerned."
Minutes later, equally upbeat Social Democrat leader Ingibjorg Solrun Gisladottir - Haarde's main rival - voted at the same primary school. "These are the most exciting elections in decades," Gisladottir said. "It's important the incumbent government loses today. We need a new, efficient, powerful, preferably left-wing, government in which the Social Democrats would be the central pillar."
This may force compromises on issues like the smelters and public spending in coalition talks expected to spill into next week or beyond if neither side wins a clear majority. "We will work with whichever party will agree with us on the issues that burn the most with us," Haarde said Friday.
He said the Social Democrats were his natural second choice. But experts see a real chance his opponents could gain enough votes to form a majority coalition and push Independence out. "I think the government parties have been losing momentum in the past few days," said Svanur Kristjansson, political science professor at the University of Iceland.