Opinion polls suggest Prime Minister Jaroslaw Kaczynski's Law and Justice party and its allies in the coalition government will do well in the countryside in voting for local councils and regional assemblies.
But the main opposition Civic Platform is expected to perform better in the big cities, engines of Poland's rapid economic growth which may exceed 5 percent this year.
The vote takes on extra significance two years after Poland joined the European Union because the winners will have a decisive say on how billions of euros from EU funds are spent on infrastructure projects over the next four years.
''We have to remember that it is the local governments which will be in charge of EU funds,'' Kaczynski told party faithful a week ago. ''This time the ballot has more weight than (the last two times they were held) four or eight years ago.'' A ban on campaigning on the eve of election day kept politicians silent yesterday.
The campaign has been dominated by how best to spend EU money and a range of local issues, though in the big cities party loyalties appear to be the major factor.
Just over 30 million people are eligible to vote to fill mayoral posts in the cities and 46,790 councillors' posts in districts, towns and cities and in provincial assemblies.
Second round run-offs will be needed on Nov. 26 in districts where no candidate wins more than 50 per cent of the vote.
Some analysts say a good result for Law and Justice may encourage it to abandon its uneasy coalition with leftist and rightist fringe parties and call an early general election.
But a big victory for Civic Platform could hurt Kaczynski's efforts to consolidate power, less than a month after reaching a deal that narrowly prevented his coalition from falling apart.
A survey by PGB polling group showed the ruling coalition with 40 percent support, ahead of the Civic Platform and their Peasant Party partners with 33 per cent. The centre left, which joined forces after a disastrous result in the 2005 general election, can count on 15 per cent of votes.
A crucial battle will be fought in the capital, Warsaw, where the mayoral race is close. Surveys show Kazimierz Marcinkiewicz, Law and Justice's popular former prime minister and acting Warsaw mayor, is running neck-and-neck with Hanna Gronkiewicz-Waltz, a former central bank chief.
The previous mayor, Lech Kaczynski, the prime minister's twin brother, owed his victory in last year's presidential election largely to his time at Warsaw city hall.
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