欧州議会議員選挙
For the first time in 2014, the President of the European Commission was appointed under the new provisions established with the Treaty of Lisbon, which had entered into force after the 2009 Elections to the European Parliament, on 1 December 2009. Juncker's aide Martin Selmayr played a central role in his campaign and later during his presidency as Juncker's campaign director, head of Juncker's transition team and finally as Juncker's head of cabinet (chief of staff).