A referendum on Scottish independence that was once expected to collapse in resounding defeat was going down to the wire Wednesday, with each side scouring lush Highland ridges, Gothic back alleys and rocky coasts seeking any advantage on the eve of a vote that could divide this island after three centuries of union.

The referendum has transfixed Scotland’s 5.3 million people, and analysts expected an extraordinary 90 percent of eligible voters on Thursday to answer a simple but far-reaching question: “Should Scotland be an independent country?”

But as much as the vote will turn on attitudes toward Scottish nationalism, it also will be a verdict on a group nowhere to be seen on the ballot: British politicians.

“It’s not that I’m against the English,” said Karen McGurk, an out-of-work mother of two who lives in state-subsidized housing on the south side of Glasgow. “But the politicians in London have behaved absolutely shockingly. They’re only for the rich.”

McGurk said she’s a firm “yes” voter, as are most of her neighbors on a block of modest red-sandstone houses that mixes working-class native Scots with South Asian immigrants. In another era, the area might have lined up firmly behind the Labor Party’s call to vote no — a position that has been joined by Britain’s two other biggest parties.

How an independent Scotland would change the United Kingdom, from nukes and oil to the flag and the queen.

But residents said they were relishing the chance to give the political establishment, Labor included, a kick in the teeth — even if it meant killing off the United Kingdom in the process.

Anger’s many roots

The anger has many roots: a seemingly unending stream of foreign wars, a financial crisis that accelerated a widening gap between rich and poor, and an insular and privileged British political class that seems to only look after its own.

“Ten years ago, I couldn’t have imagined Scottish independence. But you have this extremely complacent leadership just taking people for granted across the country,” said Jamie Drever, 37, who hadn’t been involved in a campaign before but was out knocking on doors, spreading the gospel of independence in Glasgow this week. “They’ve inherited these grand old buildings and are harking back to a Britain that no longer exists. But the reality tells us that the British economy is in the toilet.”

The sour mood has offered “yes” advocates a golden opportunity.

Alex Salmond, the tart-tongued Scottish independence leader whose working-class origins set him apart from the privileged clique that dominates politics in London, has skillfully deflected questions about Scotland’s viability by reminding voters of their antipathy for the heirs to Disraeli, Gladstone and Churchill.

In the campaign’s closing days, Salmond has the choice as one between “Team Scotland” and “Team Westminster” — the latter a reference to the palace in which London politicians ply their trade.

The three major British party leaders hustled up to Scotland last week after polls showed the referendum had slipped into a dead heat after months of comfortable leads for “no.” Salmond derided them for caring more about their reputations than they do about Scotland.

On Sept. 18, voters in Scotland decide whether or not to end their 307-year union with England and become the newest independent nation in the world. Truth Teller puts campaign ads for and against Scottish independence to the test. (Davin Coburn/The Washington Post)

“What Team Westminster seem to be concerned about is their own jobs,” he said.

Those jobs may very well be on the line. Prime Minister David Cameron could face a revolt in his Conservative Party, and calls for resignation, if Scotland splits the union.

His chief rival, Labor Party leader Ed Miliband, may have even bigger problems. Scotland has long been a reliable supporter of his left-leaning party in national elections. Without it, the remnants of the United Kingdom — England, Wales and Northern Ireland — could be Conservative territory for a generation or more.

On Tuesday, Miliband tried to campaign for “no” at an Edinburgh shopping mall, but his visit was cut short by demonstrators who heckled him with calls of “liar” and “serial murderer” — an apparent reference to Labor’s support for the wars in Iraq and Afghanistan.

The anti-London sentiment is not limited to Scotland. Polls show profound disillusionment with politics across the United Kingdom. Indeed, if Scotland breaks away, it will be the second anti-
establishment earthquake to hit Britain this year.

The first struck from the political right. In May, the anti-immigration U.K. Independence Party was the top vote-getter in European Parliament elections, breaking a more than century-long streak of wins by either Labor or Conservative in national balloting. The outcome was more symbolic than substantive because the European Parliament has little sway in domestic affairs. The anti-establishment wave in Scotland — coming from the political left — could have far more profound implications.

Without Scotland, the country left behind could be in need of a new name — South Britain has been suggested — and its identity as a global player will be badly shaken. The seat of an empire that once spanned the world would no longer control the top third of its own little island.

U.S. quiet but concerned

The United States has been reluctant to speak out on the referendum, mindful of its own history of breaking free from London. But U.S. officials worry that a yes vote could leave Washington’s closest ally distracted for years during negotiations with Scotland on the divorce, which would not become official until 2016.

Those talks would include the fate of Britain’s nuclear weapons — located north of the border on submarines based at a Scottish port — as well as Scotland’s desire to use the pound, its share of North Sea oil revenue and the future of the BBC.

British officials say they have made no contingency plans for a yes vote because they don’t expect it. But they have warned that a breakup could be turbulent — especially for Scotland.

“It’s the uncertainty that is the killer of independence,” said Alistair Carmichael, the British government’s secretary of state for Scotland. “Ultimately, people will cast a vote for what will be best for them and their families. But with that enormous amount of uncertainty, you can’t be sure what you’re buying into.”

Scottish officials, led by Sal­mond, have dismissed such comments as scaremongering. They insist that an independent Scotland would be more egalitarian and socially more just once it is free of the austerity policies imposed by London.

On the working-class streets of Glasgow this week, many voters said they trust Salmond’s assurances. But others said they still have concerns about whether taxes, health care and energy costs would change under an independent Scotland.

Marco Guarino, a 54-year-old lawyer canvassing for “yes,” answered them with a question: “If you’re undecided, ask yourself whether Westminster wants to keep us because they’re valuable to us or because we’re valuable to them.”

Many converts later, Guarino called it a night, smiling with the satisfaction that Scotland had moved just a little closer to independence.

“Everybody,” he said, “hates Westminster.”