Ursula von der Leyen’s fate hung in the balance Tuesday after she gave the most important speech of her career to convince European lawmakers she is the right person for Brussels’ top job. The 60-year-old German defence minister will replace Jean-Claude Juncker as president of the European Commission if she secures a majority vote in the Strasbourg assembly.

“The secret to happiness is freedom. The secret to freedom is courage. Let’s have courage together,” she urged lawmakers, citing the ancient Greek historian Thucydides.

If the conservative mother-of-seven loses Tuesday’s vote and the ballot could be close, Europe faces a summer of institutional infighting between parliament and the 28 EU leaders. If her victory is close, or secured only thanks to eurosceptic members, the first female head of the EU Commission will be weakened even before she takes over in November.

“It has been mentioned many times, we have only had two weeks to get to know each other. I am here,” she said rounding off her case to parliament after a speech that triggered lively debate. “A speech is just a speech, it’s limited,” she admitted, urging members to consult a hastily put together manifesto designed to answer demands from conservative, socialist and liberal pro-European parties.

She promised: “A climate-neutral Europe in 2015, a more social and competitive Europe, a Europe that makes use of its full potential. A Europe that has a new push on European democracy and a strong Europe that protects our European way of life.”

Von der Leyen has had only a short time since the 28 EU leaders nominated her to win over the main centre-right EPP, socialist S&D and liberal Renew Europe blocs she hopes will get her the necessary 374 votes. She was broadly well-received when she tried to reassure MEPs of her environmental credentials and that she would build an inclusive five-year programme.

“I will put forward a green deal for Europe in my first 100 days in office. I will put forward the first-ever European climate law which will set the 2050 target in law,” she said.

But Green leaders said her plan lacked specifics and said their group would not back her.

The nominee announced Monday she would step down from Angela Merkel’s German government this week whatever happens in the vote, underlining her European ambitions. The three mainstream groups are expected to back her, but the Greens and the far-left will not, and the vote is a secret ballot that could contain surprises.

“It will be a small ‘yes’,” one well-placed European source predicted. “She’ll be elected with fewer votes than Juncker was five years ago.”

The former Luxembourg premier received 422 endorsements, and anything less than 400 would be seen as disappointing for the Brussels-born German minister.

Another senior official said that if von der Leyen failed, outgoing Belgian premier Charles Michel would still become head of the European Council of EU leaders.

IMF director Christine Lagarde’s appointment to the European Central Bank would also remain on course, but the vacancy at the European Commission would be complicated to fill.

“Any new candidate for the European Commission presidency would have to come from the EPP family and could not be French. It would be a tricky situation, with gender balance back hanging in the balance,” he said.

The vote is scheduled to begin in the Strasbourg assembly at 6:00 pm (1600 GMT) and the result announced up to two hours later. The new head of the European Commission is due to take office on 1 November, the day after the deadline for Britain’s departure from the bloc.

He or she will have to manage the Brexit aftermath, Italy shirking its debt targets and efforts by Poland and Hungary to flout the EU-mandated rules of liberal democracy. For that, the commission president will need a reliable majority in Strasbourg, but this year’s elections threw up a more fragmented EU parliament than ever.