* Czechs vote to replace Euro-sceptic Vaclav Klaus
* Former PM Milos Zeman narrowly wins first round
* Foreign Minister Schwarzenberg surges to finish narrowly behind
* Second round result is widely open (Adds quotes, nearly complete results)
By Jan Lopatka
PRAGUE, Jan 12 (Reuters) - Former leftist Prime Minister Milos Zeman narrowly won the first round of the Czech Republic's presidential election on Saturday but will face a strong challenge from the country's aristocratic foreign minister in a run-off round.
Whoever wins is likely to take the country of 10.5 million people closer to the European mainstream after a decade in which the outgoing Euro-sceptic President Vaclav Klaus sniped at Brussels, making the Czechs an outlier in the European Union.
The post does not wield much day-to-day power but presidents represent the central European country abroad and appoint central bankers and judges. The winner will also play a moral role as a successor to the first post-communist president, the anti-communist dissident and playwright Vaclav Havel.
Zeman, a burly 68-year-old chain-smoking economist, won 24.2 percent of the vote, results from 99.9 percent of voting districts showed.
But the biggest celebration broke out at the campaign headquarters of Foreign Minister Karel Schwarzenberg, 75, who won a surprisingly strong 23.4 percent and knocked earlier favourite Jan Fischer out of the race.
The second round will take place on Jan. 25-26.
Zeman immediately attacked Schwarzenberg's record in the centre-right cabinet, unpopular for graft scandals and austerity policies that have helped protract an economic recession.
"He is a man who, as minister and first deputy prime minister, voted to raise taxes on food and medicines," Zeman said in his first remarks after the results.
Zeman built up the centre-left Social Democrat party after the 1989 end of communism and served as its first prime minister in 1998-2002, before leaving active politics for a decade.
He is popular for his sharp wit as well as a down-to-earth lifestyle and a penchant for knocking back shots of liquor at any time of day.
But many Czechs dislike him because of his allegiance to former Communist officials and businessmen with strong links to Russia, the old master of the eastern bloc.
Schwarzenberg, whose full name is Karl Johannes Nepomuk Josef Norbert Friedrich Antonius Wratislaw Mena Fuerst zu Schwarzenberg, is prince from a centuries-old aristocratic family that once owned swathes of central Europe before communist confiscations and eviction to Austria in 1948.
Currently foreign minister in the centre-right cabinet, the bow-tied, pipe-smoking Schwarzenberg is personally untainted by graft scandals. He supported anti-communist dissidents behind the Iron Curtain and served as a chancellor for Havel.
"I promise I will do all I can for us to become an orderly and successful country, a heart of Europe," he said.
Schwarzenberg won popularity among voters mobilised via social networks like Facebook, where his campaign logo featuring a man with a violet, punk-like hairstyle became a hit among young electorate.
Some voters have been turned off, however, by his alliance with the unpopular Finance Minister Miroslav Kalousek in the conservative TOP 09 party, a junior partner in the ruling coalition. Others are put off by his age and a tendency to mumble and fall asleep during meetings. (Reporting by Jan Lopatka; Editing by Rosalind Russell)