LJUBLJANA (Reuters) - The Slovenian government’s biggest investment project got majority support at a referendum on Sunday, preliminary results showed, giving a boost to the center-left government before a general election next year.

The project to build a 1 billion-euro ($1.19 billion) railway to Slovenia’s main Adriatic port was supported by 53.5 percent of voters against 46.5 percent, amid low turnout of 20.5 percent, the State Election Commission said after counting 99.7 percent of the vote.

The coalition government has said the 27-km (17-mile) rail link between Koper and the town of Divaca is necessary to speed up freight traffic to and from Slovenia’s only port and improve the port’s competitiveness.

The government has received 44.3 million euros in European Union funding for track preparation, and neighboring Hungary said it was willing to invest about 200 million euros - it relies on Koper for much of its seaborne freight.

But a civil society group, Taxpayers Don’t Give Up, demanded the referendum, claiming that the railway line as projected by the government is too expensive. The leading opposition party, the center-right Slovenian Democratic Party (SDS), also backed the referendum.

Under Slovenian law, a minimum 20 percent of some 1.7 million eligible voters would have been needed to sink the project, in addition to a majority of those voting.

“This result is a success for the government ... but the government will have to work hard to improve its ratings before the general election,” said Tanja Staric, a political analyst of Radio Slovenia.

The general election is due in June or July next year. Over the past year the opposition SDS has led in most opinion polls.

Government parties hope to improve their ratings by advancing the railway project, raising minimum wages and family subsidies and injecting more money into the state health sector in the coming months.