PARIS (Reuters) - France's presidential election looks set to become a straight fight between Socialist frontrunner Francois Hollande and incumbent Nicolas Sarkozy after both widened the gap with other contenders over the past month, a poll showed Sunday.
The survey by pollsters LH2 showed Hollande extended his lead over Sarkozy for the first electoral round on April 22 to 8.5 percentage points versus a 4.5 point gap three weeks ago.
Hollande scored 34 percent against the president's 25.5 percent, according to the poll carried out for website Yahoo! on February 3 and 4. Far right candidate Marine Le Pen is in third place with 15 percent, down 2 points, and centrist Francois Bayrou, also lost 2 points to 12 percent.
Le Pen Sunday accused the big two parties of trying to exclude her from the race.
Presidential poll graphic: http://r.reuters.com/was36s
The trend toward a two-man contest comes as both leading candidates step up their campaign efforts, even though Sarkozy is still waiting until close to a March 16 deadline before officially declaring his candidacy.
The pollsters said the two main contenders had benefited from more exposure during the recent busy political period. "While our previous studies had marked a progression of the challengers, they have now lost some momentum," LH2 said in the survey, based on interviews with 955 adults.
Hollande looked set to defeat Sarkozy in the second round with 57 percent of the vote, according to the poll.
His first big rally last month and the withdrawal of maverick left-wing candidate Jean-Pierre Chevenement from the race have helped him in opinion polls.
Sarkozy's prospects have brightened too after he announced a flurry of measures to boost employment and competitiveness.
He was also buoyed this week by securing the "active support" of German Chancellor and fellow conservative Angela Merkel, who will appear with him at events during his campaign.
A separate TNS Sofres poll for Canal+ showed that 40 percent of people had yet to decide who they would vote for.
(Reporting By John Irish; Editing by Ben Harding)