European Commission Vice President Maroš Šefčovič | Emmanuel Dunand/AFP via Getty Images Maroš Šefčovič withdraws from Socialist race for Commission top job Commission vice president says he will support his rival, Commission First Vice President Frans Timmermans.

European Commission Vice President Maroš Šefčovič pulled out from the race to become the Social Democrats' lead candidate for the EU election in May next year.

Šefčovič will back the only other contender in the race to be the political grouping's Spitzenkandidat, Commission First Vice President Frans Timmermans.

In a letter to Sergei Stanishev, the President of the European Socialist party family (PES) seen by POLITICO, Šefčovič pledged to "endorse Frans as the PES Common Candidate to be presented for a vote in order to lead our party family into the 2019 European Parliament elections."

"I stand ready to to support Frans and work closely with him," he added.

The EU's Spitzenkandidat candidate system was adopted in 2014 as a way of creating at least a veneer of democracy, and to push back against critics accusing Brussels of being controlled by unelected bureaucrats. The process allows EU-wide party groupings to nominate lead candidates for the Commission top job.

The eventual nominee must be approved by a majority in the European Parliament, but the European Council is still free to nominate an individual who did not run as a lead candidate for the post.

Šefčovič's move came after two internal party debates, the last of which happened at a meeting of Socialist leaders before the October EU summit. Šefčovič, from Slovakia, had collected the support of nine PES parties, mainly from Central and Eastern Europe. Timmermans was able to produce 12 letters of support, including larger delegations at a PES congress next month such as Germany's SPD.

Šefčovič wrote in his letter that despite his own ambition and despite the fact the he "felt a personal obligation to visibly contribute" to his party's success, he would rather close the ranks behind one candidate at a time when social democratic parties are in retreat across the Continent.

"I also understand the power of team spirit and shared goals" he said, adding he wants to "create a united front and concentrate our energy on preparing a powerful political agenda."

PES President Stanishev said in a statement: “I warmly welcome the decision of Maroš Šefčovič to endorse Frans Timmermans as the PES lead candidate. Maroš is a true team player.”

A projection by the European Parliament for POLITICO's Election Hub suggests that the EU's Socialist parties will come second in next year's election.