PARIS (AP) — France’s presidential campaign officially kicked off Monday – just 13 days before voting begins – with incumbent President Emmanuel Macron dressing down a far-right rival over unusually violent rhetoric from his supporters.

While polls suggest Macron is the front-runner ahead of the two-round election April 10 and 24, many voters remain undecided about whether to vote and for whom to vote, so the outcome remains uncertain. Macron, 44, is a centrist former investment banker who has shifted toward the right on some issues in the face of mounting pressure from conservative and far-right challengers.

Twelve candidates are in the running and have already been holding events, but under French law Monday was the official opening of the campaign. From now on, candidates can send their platforms to voters, city halls can post official campaign posters and French broadcasters must adhere to strict rules on air time for each candidate.

Macron scaled back his campaign plans because of the Ukraine war, but visited voters Monday in the Burgundy city of Dijon, meeting with students at a vocational school and a cooking school to talk about improving opportunities for young people.

The visit was overshadowed by an incident the day before, when crowds supporting anti-immigration pundit and candidate Eric Zemmour shouted “Macron, assassin!” at a rally across from the Eiffel Tower. The chant rang out loudly and repeatedly over several seconds, while Zemmour stood, silent, before resuming his speech.

His supporters were apparently responding to comments by Zemmour accusing the government of failing to protect people killed by terrorist or other attacks in France. Such attacks have hit the country throughout its history under presidents on the left and right.

Such violent language is unusual in French politics, and Zemmour’s failure to quiet the shouts drew widespread criticism from politicians across the spectrum, who saw them as dangerous for the nation. Zemmour later said he hadn’t heard the chants, and his campaign eventually condemned them.

Asked Monday about the chants, Macron said Zemmour either lacks political respectability — or is hard of hearing.

“There are two hypotheses. The first is indignity, this is the one that seems to me the most credible,” Macron told reporters. Then with a note of sarcasm, he added, “The second is a lack of knowledge about a very important reform of my term. … Hearing aids, glasses and dental implants are now reimbursed by the health care system.”

Zemmour, who has been convicted three times of hate speech, has shaken up the campaign and eaten into support for longtime far-right leader Marine Le Pen. Zemmour has notably made false claims exaggerating the numbers of immigrants and Muslims in France, and championed a baseless racist theory that non-white ethnic groups are plotting to replace white populations.

For all the candidates’ talk of security and migration, however, purchasing power is the main concern of voters.

Macron and Le Pen have focused on this, and appear most likely to make it to the decisive runoff. They are followed in the latest polls by far-left leader Jean-Luc Melenchon, Zemmour and conservative Valerie Pecresse.

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