In British election, nationalists may seize nearly all Scottish seats

* Labour could lose 37 Scottish seats - projection

* After referendum failure, SNP seek kingmaker position

* Scotland's political map faces biggest change in decades (Adds quotes from Miliband, Murphy)

By William James

LONDON, April 10 (Reuters) - A forecast on Friday showed Scottish nationalists could take nearly all the parliamentary seats in Scotland in the British election on May 7, potentially giving a party that wants to leave the United Kingdom huge influence at the heart of power.

Less than seven months since they lost a referendum on independence, the nationalists hope the likely failure of Prime Minister David Cameron's Conservatives and the opposition Labour Party to win an overall majority will put them in a kingmaker position.

Although Scots voted to keep Scotland in the United Kingdom, the Scottish National Party (SNP) has since attracted record support, partly due to anger at London's perceived failure to deliver on promises of greater autonomy given before the referendum.

A YouGov (LSE: YOU.L - news) poll for The Times newspaper found the SNP had 49 percent support in Scotland, while Labour was on 25 percent. It was the biggest lead so far for the SNP and the lowest level for Labour since 2007 in such a YouGov poll.

According to The Times, these results would translate under a uniform swing to 53 seats out of the 59 in Scotland for the SNP, just four seats for Labour and one seat each for the Liberal Democrats and the Conservative Party in Scotland.

"While local factors, including MP incumbency, are likely to lead to Labour and the Lib Dems doing better than this, even so, this looks more like a tsunami than landslide," YouGov President Peter Kellner was quoted as saying by The Times.

In 2010, Labour won 41 of the 59 seats in Scotland, the Liberal Democrats won 11, the SNP six and the Conservative Party one.

"If the polls prove to be correct on 7 May, this will represent a genuinely historic change and one of huge proportions," said Gregor Gall, editor of the Scottish Labour History Society, told Reuters.

"The referendum last year was the culmination of a long process of political disillusionment. The whirlwind from that is still being reaped for Labour."

SCOTTISH TSUNAMI?

Labour has told voters that if it loses Scotland, Ed Miliband's chances of ousting Cameron - who has admitted he is not popular with many Scots - will be undermined.

But in Scotland, even the leader of the Scottish Labour Party, Jim Murphy, says that Labour faces an uphill battle after years of what many Scottish voters see as neglect by the main political parties in London.

Nationally, one online poll give Labour a UK-wide lead of six percentage points but Miliband visited Scotland on Friday in the hope of reviving his party's fortunes.

At a news conference in Edinburgh, Miliband was asked by reporters whether his party was facing a wipe-out and whether he was more of a hindrance than a help to Labour activists in Scotland.

"We are setting out the big election choice, the real choice at this election: You either have a Labour government or a Conservative government," Miliband said.

He said he believed many voters had yet to make up their minds in the election.

Appearing at the news conference beside Labour's finance spokesman Ed Balls and the leader of the Scottish Labour Party, Jim Murphy, Miliband said he would spend more time in Scotland ahead of the vote.

"David Cameron can't win seats in Scotland so he needs someone else to beat the Labour Party," Murphy said. "He is like cheering on the SNP each and every day because he can't win and he is using the SNP as his little helpers in this election."

SNP leader Nicola Sturgeon on Tuesday raised the prospect of another independence referendum after the 2016 Scottish election. She said on Wednesday a referendum on EU membership, which Cameron has promised should the Conservatives retain power, could trigger another Scottish vote.

Miliband has dismissed a formal coalition with the SNP but has not ruled out a less formal arrangement. The SNP has said it wants more powers for Scotland and more spending, and that it would reject the renewal of Britain's nuclear arsenal. (Writing by Guy Faulconbridge; Editing by Angus MacSwan)