The Remain camp has managed to persuade more voters of the merits of staying in the EU after the government's controversial £9m leaflet was sent to households across the UK.
Indeed, the latest ORB poll has found that there is a growing majority preference among voters for continued membership of the EU.
But with fewer people left undecided, the referendum is still likely to be determined by which side can better get its supporters to turn up on the day and cast a vote.
Pro-EU groups will then be even more encouraged by the poll finding that those who want to remain in the EU are becoming more motivated to vote.
Turnout overall is up three points to 67 per cent, according to the poll. The turnout rise is completely due to an increase in motivation among Remain voters.
Some 65 per cent of Remain voters are now motivated to vote (up four points). Contrastingly, there has been no change in motivation among Leave voters, with 70 per cent saying that they are definite to vote on 23 June.
Put together, Remain currently leads with 52 per cent of the vote, up three percentage points since the last poll, while Leave has fallen five percentage points to 43 per cent.
The findings of the poll also suggest that the Remain campaign is making the most of the economic argument.
However, the Leave campaign is not making the most of the issue of immigration. In particular, Leave could benefit from advocating changes that would result from Brexit and making immigration more important in voters' decision making.
That could indicate why justice secretary Michael Gove will today criticise the government over its "admission" that it can't control immigration after a Treasury report said three million more migrants will arrive in the UK by 2030 if the country remains in the EU.
"Over 250,000 people came to Britain from Europe last year. As long as we are in the EU we cannot control our borders and cannot develop an immigration policy which is both truly humane and in our long term economic interests," Gove will say.