Fenby said that many of the candidates represented the "old political establishment" that French voters were rejecting.
"(The candidates) are all 'former something' -- 'former prime minister' or 'former this or that.' Sarkozy is trying a comeback and the paradox is that most of the French voters are rejecting the old establishment. But Juppe, who appears to be the frontrunner in the polls, is Mr Establishment."
Challenging the center-right and right-wing parties for votes is Marine Le Pen, the head of the anti-immigration and euroskeptic Front National (FN) party.
Le Pen is expected to get through a first round of the presidential election and is expected to face a center-right adversary in the final run-off – such as Sarkozy or Juppe.
France operates a two-round system in which candidates have to win 50 percent of the vote to pass through to a second-round of voting which then determines a single winner. Fenby explained that Le Pen's current popularity in the polls meant that she stood to face a center-right candidate in the run-off. French President Francois Hollande, of the Socialist party, has yet to say if he will run again for the leadership but his low approval ratings mean his chances of re-election are slim.
"It's almost certain that Le Pen will finish in the top two in the first round of the presidential election," Fenby said. "Remember this is a two-round election (so) Le Pen will finish top with around 30 percent (of the vote) -- so the important thing is who finishes up there with her. So really this Republican primary in November is a kind of presidential election in advance, because the left really doesn't have much of a chance."
Fenby said that the rise of the right had come as the Socialist party had proved itself to be anemic in power with economic reforms slow to materialize and the economy slow to recover.
"What you've got in France is the complete decline of the center-left…so you've got no answer to this right and extreme-right surge in France," he said.
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