Arnaud Montebourg and Audrey Pulvar, a prominent broadcaster, said a group of about 15 men surrounded them as they left a restaurant late on Tuesday and shouted "Le Pen for president", referring to far-right leader Marine Le Pen.
They also shouted "France for the French" and "Juden, Juden, Juden" (which means Jews in German) before throwing glasses at the couple as they left the restaurant in Paris' chic 16th district, Pulvar said in Twitter messages.
The incident came just days after Pulvar gave Le Pen a grilling in a weekend television show about her alleged association with European neo-Nazi groups.
"This shows that there is a climate within Mrs Le Pen's (National Front) where racist speech is made freely," Pulvar told AFP.
Le Pen, who opinion polls put in third place in the presidential vote in April and May, said "obviously I condemn this type of aggression."
But she added: "You cannot consider, before the police have done their work, that these people are people from the National Front."
François Hollande, the Socialists' presidential candidate, condemned the attack on Pulvar and Montebourg, who stood against him in a party primary last year to pick a contender for the presidential vote.
"It is unacceptable to attack a person for his ideas and to do it in a cowardly manner with shouts, insults, with glasses thrown and with remarks that border on anti-Semitism and racism," he said.
An opinion poll published on Tuesday by IFOP said Hollande would take 28.5 percent of the vote in the first round, against 27 percent for President Nicolas Sarkozy.
Le Pen would come in third place in the first round with 17 percent, the poll said.