* Euro crisis deal-broker submits candidacy
* Rivals include Latvia's Dombrovskis, France's Barnier
* Centre-right group EPP to chose lead candidate in March
BRUSSELS, Feb 27 (Reuters) - Veteran Luxembourg politician Jean-Claude Juncker has entered the race for the post of European Commission president, officially submitting his bid on Thursday to become the centre-right political group's candidate.
The move, which had been expected, puts one of the European Union's most experienced deal brokers in the frame for arguably its most influential job although Juncker, who once told a conference he sometimes lied and favoured "secret, dark debates", has alienated some by his frankness.
The European People's Party (EPP) announced the former Luxembourg prime minister's candidacy that will see him compete with Valdis Dombrovskis, previously Latvian prime minister, for a post with power over policy affecting 500 million Europeans.
Michel Barnier, the European commissioner who oversaw banking reform, is also expected to seek backing from the centre-right EPP, when members meet to chose their lead candidate ahead of the European Parliament elections in May.
Unlike his two rivals, however, Juncker has the backing of German chancellor Angela Merkel, bolstering his chances of success when the EPP, Europe's largest political grouping, gathers on March 6-7 in Dublin.
Part of a generation of old-school politicians, Juncker played a significant role in handling Europe's debt crisis, leading the Eurogroup of euro zone finance ministers.
For decades, elections to the European Parliament have been a secondary affair, with a low turnout. That has changed since the introduction of a new EU treaty in 2009, which gave the parliament more say in policy and a role in determining who should become the Commission president.
And following the worst financial crisis in a generation, many observers expect radical nationalist parties to win unprecedented support when voters from across the 28-member European Union go to the polls.
Whichever political group emerges as the largest bloc in parliament following the May 22-25 elections is expected to have first claim on the presidency post, although the choice also has to be approved by EU leaders.
A new Commission president - replacing Jose Manuel Barroso who has held the post since 2004 - will take office for five years from November, taking charge of an institution responsible for proposing EU law and policing existing rules.
The Commission also leads trade negotiations and coordinates foreign policy.
Juncker was caught up in a spying scandal in Luxembourg last year and his Eurogroup successor and Dutch finance minister, Jeroen Dijsselbloem, described him on Dutch television as a heavy drinker and smoker. Juncker has dismissed these suggestions.
He disarmed but often irritated ministers with his dry sense of humour, speaking openly of having to lie to the media and discussing his problems with kidney stones.