ATHENS, Greece -- Conservatives made strong gains in local elections across Greece but fell short of the overwhelming victory they needed to force the long-governing Socialists to call early national elections, results showed Monday.

With more than 95 percent of the vote counted, the center-right New Democracy party held huge leads in mayoral races for Athens and other cities. It also took a commanding lead in contests for regional governorships.

The far right also made surprising gains, with an ultra-nationalist candidate garnering 13.6 percent of the vote in a race for regional governor of greater Athens. It was the best showing for a far-right candidate since the 1980s.

Most contests will be settled in run-off elections on Oct. 20 because candidates must collect at least 50 percent of the vote to win.

New Democracy leader Costas Caramanlis said after Sunday's vote it was clear the party was the biggest political force in the country. "The government refuses to accept this message," he said. "It is a hostage of its own arrogance."

In Athens -- a high-profile race ahead of the 2004 Olympic Games to be held there -- conservative Dora Bakoyianni led with 47.4 percent. She is the favorite to become the first woman mayor in the run-off.

Conservative candidates won outright in northern Thessaloniki, Greece's second largest city, and received just under 50 percent in the main port of Piraeus.

The vote covered three metropolitan prefects, 54 regional prefects and 1,033 mayors. A prefect acts as a regional governor, but with limited powers.

New Democracy won 13 prefectures outright -- compared to nine after the first round in 1998 local elections.

The results follow a bitter campaign, with New Democracy urgin voters to turn their backs on the government of Premier Costas Simitis. It described the municipal poll as a referendum on the Socialist party, which has been in power for all but three years since 1981.

National elections are scheduled for 2004.