Sept 28 (Reuters) - French far-right candidate Marine Le Pen and far-left contender Jean-Luc Melenchon are seen reaching a run-off vote in next year's presidential election in each of five scenarios polled, according to a survey published on Monday.
The results of the poll suggest that French voters may face a contest between extremes in the election, set for next April and May, with centrists falling behind at a time of rising prices, a sluggish economy and geopolitical instability.
Le Pen, who leads the far-right National Rally (RN), is seen winning 35% to 36% in the first round, the Toluna Harris Interactive poll showed, up from 33% in an earlier poll published on September 14.
Melenchon, of the France Unbowed party, would join Le Pen in the second round, winning between 17% and 18%, according to the survey, which was conducted from September 22 to 24 for French TV channel M6 and Luxembourg-based media group RTL.
Leading centrist hopeful Edouard Philippe was seen winning 13% to 16%, not enough to reach the run-off.
Le Pen is seen beating both Melenchon and Philippe in the second round. She would win 69% of votes against Melenchon and 57% against Philippe, according to the survey.
(Reporting by Mateusz Rabiega in Gdansk
Editing by Gareth Jones)