LONDON (Reuters) - Support for Britain to stay in the European Union has risen two percentage points to 53 percent, according to an ORB opinion poll which Prime Minister David Cameron's election strategist said showed the "In" campaign was starting to win over voters.
The Telegraph said support for leaving the 28-member bloc in a June 23 referendum had fallen by three percentage points to 41 percent since an earlier ORB poll published on April 5.
Cameron's election strategist Lynton Crosby said opponents of EU membership were more motivated to turn out to vote but that the poll showed there was a growing preference among voters for staying in the club Britain joined in 1973.
"The Remain campaign has also persuaded more voters of the case for staying in the EU," Crosby, who helped Cameron unexpectedly win outright victory in a national election last May, said in a commentary for The Telegraph.
Crosby said the proportion of those saying "In" is running the better campaign has increased by 5 points to 39 percent while those saying the same of the "Out" campaign fell by 10 points to 25 percent.
Crosby said the government's 9.3 million pound ($13.3 million) leaflet setting out the case for staying in the EU may have helped boost support as could a row between the rival "Out" campaigns over the Electoral Commission's designation of Vote Leave as the official "Out" campaign.
"It may also be a derivative effect of the contrast between David Cameron's demonstrated urgency and focus on the outcome, and infighting between various Leave factions over which campaign should receive the official designation," Crosby said.
Crosby said immigration was an issue the "Out" campaign could use to win over voters while the "In" campaign could lose support if it could not convince voters that the EU helped job creation.
Six percent of those questioned said they did not know how they would vote. The Telegraph said the poll surveyed 800 people but did not give any further details.
Reporting by Guy Faulconbridge; editing by Kate Holton