Weber hopes to use the elections as his springboard to the presidency of the European Commission.
"The campaign starts here in Helsinki," Weber told the EPP delegates on Thursday. "We are bridge-builders, let's use this momentum. Then we will win in May 2019," he said.
Weber won a decisive vote against former Finnish Prime Minister Alexander Stubb at the EPP congress in Helsinki on Thursday. Weber was considered the favorite despite the fact that the 46-year-old only has basic French and barely fluent English. Stubb is fluent in English, French and German.
Some members of the European Parliament see his language issues as a significant drawback; traditionally the heads of the Commission, a sprawling bureaucracy that employs more than 32,000 civil servants, speaks English and French in addition to their mother tongues.
Weber took over the chairmanship of the EPP Group in the European Parliament, in 2014. He is regarded as somewhat of a balancing act, who can quietly hold together the "flea circus" of the conservatives with a soft touch.
The 219-member EPP includes the full spectrum of the EU right, from Hungary's nationalist Fidesz to the more laissez-faire Belgian parties. Weber's pro-Europe stance is often at odds with his own party, the CSU, which is why its members were reluctant to put him forward as a top candidate in the 2014 campaign for the European Parliament.
Regarding migration, Weber skillfully maneuvered between the position of German Chancellor Angela Merkel of the CDU and the views of Horst Seehofer, the leader of the CSU. By doing so, Weber was able to keep 11 Hungarian anti-EU Fidesz MEPs from abandoning the EPP.
Weber, a Catholic who is firmly anchored in the executive committees of the CSU, managed to garner Merkel's support for his candidacy.
Without the chancellor's approval, Weber would have zero chance of victory in elections for the European Parliament and in his efforts to become president of the Commission.
It has been reported that Merkel and Emmanuel Macron have agreed that in 2019 a German would take over the presidency of the Commission and that the next leader of the European Central Bank (ECB) would come from France. Merkel has refused to officially comment on any such deal-making in Brussels.
The unknown legislatorWeber remains relatively anonymous outside the Brussels bubble and his constituency in Bavaria.
Many representatives from smaller EU countries have doubts about whether appointing a German to the top office of the European Commission is a good idea. In their eyes, Germany, the European Union's largest member, and the primary contributor to the EU budget, could become too dominant. A German has not been at the helm of the European Commission since Walter Hallstein in 1967. At the time, pressure from France meant Hallstein decided not to run for re-election.
It is uncertain how the populist coalition government in Italy will react to a German candidate. After all, both the anti-establishment 5-Star Movement and the far-right League blame Germany and Merkel for all manner of EU woes.
Weber's long roadAfter graduating from university in 1996, Weber founded a consultancy for environmental technology and remains the managing director, according to his official website.
Weber led the CSU's youth wing before serving in Bavaria's state parliament in 2002. In 2004, he was sent to Strasbourg to begin his career in the European Parliament. At first, Weber had seemed a little alienated by the legislature's bureaucracy, and he continued to run his company on the side.
In Germany, Weber made a name for himself in the CSU with his clear positions on domestic issues, and he was eventually appointed Seehofer's deputy. Weber has, however, never held a government office or led a ministry in Germany or at the state level.
Weber's critics like to contrast the lawmaker's career with those of the recent presidents of the Commission: Jean-Claude Juncker, Jose Manuel Barroso and Romano Prodi were, respectively, the prime ministers of Luxembourg, Portugal and Italy, and therefore understood the dealings of the European Council and the representation of the member states.
No guaranteesWho will eventually be elected to the European Parliament in May 2019 is impossible to predict as the far-right gains power across the EU.
It is unlikely that the EPP and the rival Progressive Alliance of Socialists and Democrats (S&D) would have the numbers to renew their grand coalition. And even a grand coalition offers no guarantees for Weber - Germany's Social Democrats in the European Parliament have already said they would not vote for him to lead the Commission.
What Macron's new center-right En Marche party will do is also unclear. The French president has already insisted that the top candidate of the winning bloc should not automatically be picked to lead the European Commission.
After Brexit takes effect next year, the 27 EU heads of state and government will have the right to nominate their own candidates. Weber is just at the beginning of a long election campaign without a foreseeable outcome.
The odds that he will succeed Juncker, who was the prime minister of Luxembourg for nearly two decades and speaks four languages, are fair to middling. But Weber may walk away with a reasonable consolation prize: He could be elected president of the European Parliament.
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