It is three months since Ipsos MORI last conducted a poll of voting intentions in the referendum. Although the company is one of the pollsters who have tended to produce relatively low estimates of the Yes vote, that previous poll was disappointing for the Yes side, even by the standards of those pollsters that paint a less optimistic picture for the Yes side. Once the Don’t Knows were excluded it put the Yes vote at just 36%, down one point on the company’s previous poll shortly before Christmas and making it one of only two polls conducted by any company this year to have put the Yes vote below 40%.

It thus should not come as much of a surprise that Ipsos MORI’s latest poll for Scottish Television, the first to be conducted since the European elections, should have recorded an increase in Yes support. This is now put at 40% (once Don’t Knows are excluded), the highest Yes estimate the company has yet produced. However, this simply puts Ipsos MORI more or less in line with the most recent readings of the two other companies that tend to produce less optimistic figures for the Yes side, TNS BMRB (41%) and YouGov (42%). So the poll probably does little more than bring further evidence to bear in support of the now well-established story that support for independence rose in the early months of this year, a gain that so far shows no consistent sign of being reversed. Our Poll of Polls is unchanged.

At the same time, we are still left with a picture whereby three pollsters suggest the Yes vote is the low 40s while three others (Panelbase, Survation and, its most recent poll apart, ICM) tend to put it at more like 45%. In short we remain unsure whether No still enjoy a relatively comfortable lead or whether the Yes side are at least within sight of the winning post.

Nearly all of the movement since Ipsos MORI’s last poll has occurred amongst men, with the result that this latest poll has a particularly large gender gap. Men are in fact split 50:50 between Yes and No, while women are two to one against independence.

Meanwhile there are signs in today’s poll that voters are gradually being caught up in the referendum debate. First, more people than ever before , 82%, say they are certain to vote; the previous all-time high in Ipsos MORI’s polls was 79% back in December. Even though reported propensity to vote is now so remarkably high, Yes voters (87% certain to vote) remain slightly more inclined to vote than No supporters (84%).

Second, fewer people than ever before, just 18% of all those with a voting intention, now say that they might change their mind. That represents a drop of no less than eight points as compared with Ipsos MORI’s last poll in February and no less than 12 points as compared with September last year. It seems that minds are beginning to be made up – which for the side that is still behind in the polls could be thought to be unwelcome news.