Francois Fillon, former French prime minister, member of The Republicans political party and 2017 presidential candidate of the French centre-right, attends a political rally in Charleville-Mezieres, France, February 2, 2017. REUTERS/Christian Hartmann Francois Fillon fought to keep his place as French conservative presidential candidate on Friday amid sliding opinion poll ratings and speculation about his ability to carry on after accusations his wife got public money for work she did not do.