There is just over a week and a half to go until the referendum and the No and Yes campaigns are neck and neck in the polls.

To be fair to Better Together, which until recently had what appeared to be a comfortable double-digit lead, its leaders always said it was going to be close and so it has proved. They should be nervous of what could happen in the next few days.

However, the Yes campaign, despite its apparent success, has some cause to be nervous too. The polls have been extraordinarily volatile in recent weeks, which may make talk of victory premature. There is the possibility of the campaign peaking too early (a rock many campaigns, including the Yes campaign in Quebec, have crashed on before). And it should be remembered that thousands of postal votes were cast at a time when No was in the lead.

Whatever happens in the end, the Yes campaign has been well-organised. The Scottish Government's White Paper on independence may have left many questions unanswered, but it gave the campaign a foundation on which to build. The campaign has also succeeded in creating the impression of unity among many disparate elements under the Yes banner and the grassroots campaign has been passionate and persistent.

The contrast with Better Together could not be greater, with voters struggling at times to see the togetherness. Indeed, the campaign has often felt more like a Labour General Election campaign than a cross-party fight for the future of the country. On the Yes side, SNP banners have been all but invisible, but the No campaign has often been a sea of Labour red.

The challenge now for Better Together is to create this missing sense of unity around a common message. As the Chancellor George Osborne conceded this weekend, there is a desire for more powers for the Scottish Parliament and the No campaign is right to respond with the announcement of an all-party plan to devolve further powers.

According to Mr Osborne, this would mean more tax and spending powers, and more control over welfare. When the announcement is made in the next few days, the timetable by which it will all happen will also be made clear. It could be the last chance of the No side to secure a win.

The critical question (and it is one that may decide the referendum) is whether the announcement will appeal to the Labour voters who are being attracted by the Yes campaign. As early as July, when No still had a comfortable lead, there was polling evidence of a significant rise in support for Yes among voters who supported Labour in the 2011 Holyrood election, and the Yes side has been effective in reaching these voters.

The No side, even though it has been led by Labour, would appear to have done less well in reaching them. But there is still time if Better Together emphasises greater powers, and keeps the message positive. In the recent television debate, Alistair Darling devoted much of his time to criticising the Yes campaign. It has not worked. Better Together must do better if it wants to secure a win.