French presidential front-runner Emmanuel Macron went on the hunt for blue-collar votes on Wednesday as he planned to meet with workers at the troubled Whirlpool plant in his hometown of Amiens, in northern France.

However, rather than smiles and handshakes, the banker-turned-politician was greeted to a chorus of jeers and chants backing his rival, National Front head Marine Le Pen. 

Macron's visit had been upstaged by the far-right candidate, who made a surprise visit to the same factory just hours earlier as Macron was meeting with union representatives from the plant at a local Chamber of Commerce.

Addressing a crowd of workers later on, the former economy minister said: "I am here to speak to you. Of course, there is anger in this country, there is anxiety. Responsibility must be taken, that's why I'm here."

The factory in Amiens, where the production of dryers is due to stop this year and shift to Poland, joins a growing list of threatened plants that have become symbolic in French presidential election campaigns.

Le Pen, meanwhile, vowed to keep the Amiens plant open if elected.

Read more: What you need to know about the French presidential election

"When I heard that Emmanuel Macron was coming here and did not plan to meet the workers, did not plan to come to the picket line but would shelter himself who knows where in the chamber of commerce ... I considered it was such a sign of contempt for the Whirlpool workers that I decided to ... come here and see you," she said.

Posting photos of herself in the carpark with factory workers Le Pen wrote on Twitter: "In Amiens where I went to meet and support Whirlpool employees. With me, your factory won't close!"

Macron hit back at that Le Pen saying she had only spent 10 minutes in front of cameras in the parking lot while he spent one hour and 15 minutes working with trade unions, without the press.

With less than two weeks until he faces Le Pen in France's presidential election run-off, Macron hoped to sell the benefits of globalization to an electorate that equates it with job loss and has, instead, more in common with Le Pen's protectionist, nationalist vision.

- Macron leads in polls as France prepares to vote in runoff elections

- France's election and the EU

Needing millions more votes to beat Macron, Le Pen has been hammering hard her claims that more French jobs would be lost overseas under the former investment banker's more economically liberal program.

Learning from past mistakes

The pro-EU centrist's discussions with union workers did not come without risk, however, with Macron forced to walk a fine line between defending his program to tackle France's chronic unemployment without falling into the trap that befell winners in previous elections of struggling to keep campaign promises.

In the 2012 presidential race, Socialist candidate and current President Francois Hollande traveled to a closure-threatened steel works in a similar pursuit of blue-collar votes in his ultimately successful bid to defeat then-incumbent Nicolas Sarkozy.

Union leaders later accused Hollande of betrayal when the Hayange plants' blast furnaces were shut down, in a deal struck with steel giant ArcelorMittal.

Macron was also scheduled to hold a rally in Arras, a city in the northern rustbelt where Le Pen topped the first round of voting on Sunday. Nationwide, Macron came first with 24.1 percent of the vote, with Le Pen following behind in second on 21.3 percent.

The latest Opinionway poll on Wednesday suggested that Macron will thrash Le Pen in the May 7 run-off with a margin of some 20 points.

However, after the political shocks of the Brexit referendum last June, followed by Donald Trump's unlikely election as US president five months later, analysts say a late surge by Le Pen cannot be ruled out.

In an unexpected move on Monday, the right-wing populist also stepped down as leader of her National Front (FN) party claiming that the decision would allow her to be "a president for all French people."

Read more: France faces existential questions ahead of final vote

Hollande urges ministers to vote Macron

Outgoing President Hollande told government ministers on Wednesday to do all they can to ensure the biggest defeat possible for Le Pen.

Hollande asked ministers "to fully commit themselves in the election campaign to ensure that Le Pen has the lowest possible score," said spokesman Stephane Le Foll.

Sarkozy: 'A choice of responsibility'

Former president Sarkozy also confirmed on social media that he would be casting his ballot for Macron in the presidential run-off.

"I consider that the election of Marine Le Pen and the implementation of his project would have very serious consequences for our country and for the French," Sarkozy wrote on Facebook.

"Therefore, in the second round of the presidential election, I will vote for Emmanuel Macron. It is a choice of responsibility that is not in any way a support for his project."

Cyberattacks on Macron campaign

As Macron sought to woo the working voters in Amiens, his campaign team confirmed that he had been the target of at least five advanced cyberattack operations since January

"Emmanuel Macron is the only candidate in the French presidential campaign to be targeted," Macron's "En Marche!" party said in a statement.

"It's no coincidence if Emmanuel Macron, the last remaining progressive candidate in this election is the priority target."

Read more: Suspected Russia hackers 'targeted Macron campaign'

The campaign team added, however, that no data had been compromised any campaign data.

As evidence, Macron's campaign cited results of a study by security firm Trend Micro, which said it had found proof that the spy group, dubbed "Pawn Storm," had targeted the "En Marche!" campaign.