French prosecutors on Friday appointed a magistrate to investigate allegations concerning presidential candidate Francois Fillon and his wife, over charges that his wife got large sums of money for work she may not have done, Reuters reported. The prosecutor's decision to open up a new stage in the case marks a blow for Fillon, whose status as favourite to win the presidency has faded since a newspaper broke what has become known as "Penelopegate" after his British wife. By involving a magistrate in what had so far been a preliminary probe led by police, the prosecutor is putting more resources into the investigation. The magistrate has more powers to investigate, including tapping phones or placing suspects under house arrest. The judge can still decide to drop the case, place the suspect under formal investigation, or send it to trial. It remained unclear if the probe could be concluded before the presidential election, scheduled for April 23 and May 7. Fillon has denied any wrongdoing. Under French law, the investigation would be suspended for the five-year presidential term should he be elected. The prosecutor's statement was issued as Fillon himself was set to take the stage at a campaign rally near Paris.