"In" leads by a whisker in latest Brexit poll from YouGov

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LONDON, April 15 (Reuters) - The "In" camp holds a one-point lead ahead of Britain's June 23 referendum on whether the country should remain in the European Union, according to an online opinion poll by YouGov (LSE: YOU.L - news) released on Friday.

The poll found support for "In" stood at 40 percent, while 39 percent intended to vote "Out", 16 percent were undecided and 5 percent did not intend to vote.

The poll of 3,371 people was conducted between April 12 and 14 and the results were similar to those seen in other recent YouGov polls. The previous one, conducted on April 11-12, found "In" and "Out" were tied on 39 percent with 17 percent undecided.

YouGov said that the average from its polls in the last six weeks was a two-point lead for "In".

Online polls have tended to produce results suggesting the race is very tight, while telephone polls have tended to find "In" ahead by more comfortable margins. Experts have suggested explanations for the discrepancy but there is no wide agreement on which set of polls, if any, is correct.

The latest YouGov poll, for ITV (LSE: ITV.L - news) 's "Good Morning Britain" programme, also found that when those surveyed were asked how sure they were of which side they would back, the proportion who were not completely decided rose to 42 percent.

YouGov also asked those interviewed how they would vote if leaving the EU meant Britain's standard of living would fall and people would be worse off by an average of 100 pounds ($142)a year.

In response, 45 percent said they would vote to remain, 36 percent to leave and 14 percent said they were undecided.

"The result reveals the potential for so-called 'project fear', the most popular - and much criticised - strand of argument for Remain in the campaign thus far," said YouGov's Will Dahlgreen on the pollster's website. (Reporting by Estelle Shirbon; editing by Stephen Addison)