If, as seems to be the case (see previous post), the serial killer is a Muslim of North African descent, the impact on the election could be significant. Anti-Muslim sentiment could be exacerbated, and Sarkozy's tilt to the far right might yield unexpected dividends. In any case, one can only hope that the right man has been found and will be brought to justice quickly.
Ths Le Point story suggests that the police have the murder weapon, which confirms that they have located the right man. He had been under surveillance by several intelligence services because of his having spent time in tribal regions on the AfPak border.