With 24 hours until voters go to the polls in Scotland, the Nationalists are still clinging to a lead over Labour, The Times’s latest opinion poll shows – but the gap is narrowing.

The Populus poll points to the probability of devolved Scotland being governed by either an SNP-Liberal Democrat coalition or a third consecutive Labour-Liberal Democrat partnership, with Nicol Stephen, the Scottish Lib Dem leader, as the potential “kingmaker”.

The survey suggests that the recent pro-Union barrage by Tony Blair and Gordon Brown, portraying the Nationalists as having a “tax and turmoil” wrecking agenda if they win, has had only limited success.

However, with about one in ten voters still undecided, the poll will also induce some nervousness within the SNP. Another poll, by ICM for The Guardian and The Scotsman, also shows that the SNP lead over Labour has shrunk and has Labour winning the most seats.

But, according to Populus, the Nationalists are still on course to become the largest party in Scotland’s Parliament with Alex Salmond favourite to become First Minister and able to prepare the ground for a referendum on Scottish separation in 2010.

Other findings by Populus indicate that support for outright independence has slipped again among Scots – down one point from 22 per cent 12 days ago to 21 per cent now.

On voting intentions, the poll gives the SNP 33 per cent support on the constituency vote, down one percentage point since mid-April, with Labour on 29 per cent, also down one. The Liberal Democrats are on 15 per cent in the constituency section, down three, and the Conservatives are flatlining on 13 per cent. The number of respondents saying that they will use their constituency vote for other parties has gone up four percentage points to 10.

The poll suggests that the Nationalists would have 45 seats, one fewer than Populus gave them 12 days ago and Labour would be just behind on 43, one more than 12 days ago.

The Liberal Democrats would have 23 seats, the same estimate as in mid-April, and the Conservatives would have 17, again the same as 12 days ago. The Greens would have one MSP and the other parties and independents none.

Signs of a late surge in nationalist support in Wales have forced Labour to rethink its election strategy.

Rhodri Morgan, the Labour First Minister, switched tactics to concentrate on attacking Plaid Cymru in the final days after two polls picked up big swings to the nationalists.

The most detailed poll, by ITV Wales, puts Labour down 4 points on 32 per cent, Plaid up 6 on 20 per cent, the Tories down 4 on 19 per cent and the Lib Dems steady on 15 per cent.

The poll projected that, in the 60-member Welsh Assembly, Labour would have 25 seats (down 4), Plaid Cymru 15 (up 3), the Conservatives 10 (down 1) and the Lib Dems 8 (up 2).

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