Scotland: Who’s likely to vote Yes or No

The increasingly bitter Scottish independence referendum campaign, which enters the home straight today ahead of Thursday's polling, has been fought on social and gender lines.

While there is no typical Yes or No voter – and there is still a large number of crucial undecided voters, as much as 14 percent, there are some patterns from polling so far which suggest that certain groups are more likely to vote one way or another.

Women

Women are more likely to vote "No" than men, with polls suggesting around 56 percent of Scottish women back the No campaign. They're also less certain of the consequences of independence - just 27% of women said they were sure what independence would bring, compared with 37% of men, according to a poll in August by ScotCen Social Research, a Scottish independent research body – and voters who feel uncertain are less likely to back the idea, data from the Quebec referendum in 1995 suggests.

Lower income

In the more deprived parts of Scotland, where people are less likely to feel strong ties to the U.K., there is stronger support for a Yes vote.

"Missing million"

The Yes campaign has focused on getting the so-called "missing million" of Scots who don't usually vote out to the polling booth – and claims that pollsters have not taken enough account of these voters. With 97 percent of the eligible population now registered to vote in the referendum, the turnout is likely to be substantially higher than a typical general election.

Over 65s

Fond of the status quo, and worried about what might happen to their pensions in the event of a Yes vote, polls have suggested the over 65s are much more likely to back the No campaign.

Under 25s

Young Scots – including the 16- and 17-year-olds who Alex Salmond lobbied to have included in the referendum (the usual voting age in the U.K. is 18) – are much more supportive of the Yes campaign than their older counterparts.

Conservative voters

As the cliché goes, there are more pandas than Conservative Party MPs in Scotland. Yet the right-leaning party, led by Prime Minister David Cameron, still has the support of around 15-17 percent of those who voted in the last election in Scotland, and they are natural No voters.

Middle classes

Much more likely to listen to the negative messages about Scotland's economy if there is a Yes vote than those further down the social scale, polls suggest.

Immigrants

One aspect of the poll frequently complained about by Scots living in the rest of the U.K., is that the close to a million Scottish residents born elsewhere in the U.K. or outside it can vote in the referendum. However, based on those polls which have broken down the voting intentions of those born outside Scotland, these voters are much more likely to either vote No or not vote at all.

- By CNBC's Catherine Boyle