BRUSSELS (Reuters) - The center-right is set to win the most seats in European Parliament elections next week, but its wafer-thin poll lead suggests the chances of securing the presidency of the European Commission are uncertain.
The European People's Party (EPP) will take 212 seats in the May 22-25 vote, according to an analysis of national polls on Wednesday by PollWatch 2014, only three more seats than its center-left rivals, the Socialists and Democrats (S&D).
There are 751 seats in the parliament, around 70 percent of which are expected to go to Europe's four mainstream groups - the center-right, center-left, Liberals and Greens.
Around a quarter of seats look likely to be won by anti-EU or protest parties on the far-right and far-left, almost double their standing at the last election in 2009. That's largely because of voter frustration with high unemployment and low growth.
Under EU rules introduced in 2009, the party that wins the election is best placed to have its top candidate become the president of the European Commission, one of Brussels' most powerful jobs, with far-reaching influence over legislation.
But while the EPP may just edge out the Socialists in the vote, according to Wednesday's survey, the Socialists are better placed to secure allegiances with other parties on the left, potentially helping them secure a majority in parliament.
Since the nominee for Commission president must be approved by parliamentary majority, the Socialists may be able to argue that their candidate has greater legitimacy than the center-right EPP's.
The nomination for Commission president will be made by EU leaders, who are required to "take into account" the results of the election in making their choice.
The EPP has chosen Jean-Claude Juncker, 59, the former prime minister of Luxembourg and a central broker during the euro zone debt crisis, as their candidate to succeed Portugal's Jose Manuel Barroso, who has led the Commission since 2004.
The Socialists are backing Germany's Martin Schulz, 58, the current head of the European Parliament and an ardent campaigner for more money to be spent helping young people get jobs.
The Alliance of Liberals and Democrats, known as ALDE, have chosen former Belgian Prime Minister Guy Verhofstadt as their candidate for Commission president. But PollWatch's latest survey sees the Liberals taking just 63 seats.
None of the three candidates would sail past the EU leaders, with Britain in particular wary of any candidate deemed too much of an integrationist.
All three main parties will likely lose seats in the new parliament at the expense of the far-left and far-right, although it remains unclear how coordinated groups on the right and left will be and therefore how influential.
"Compared to the outgoing parliament, the new parliament would be more polarized, with more (EU lawmakers) on the radical left and on the right," PollWatch said in a statement.
The group forecasts that if the far right forms an alliance that included France's National Front and Geert Wilders' Party for Freedom in the Netherlands, it would win enough seats to form a group, meaning access to EU funds and greater influence.
The UK Independence Party (UKIP), which wants Britain to leave the European Union, could lead another anti-EU group with 64 seats, according to PollWatch's analysis, enough to secure the chairmanship of a committee in the parliament.
PollWatch, part of an initiative to track the trends and votes in the European Parliament, gathers opinion poll data and uses a model to estimate support for parties in the elections.
Reporting by Robin Emmott Editing by Jeremy Gaunt