The Bellwether Seats: Five Constituencies Which Will Decide the UK Election

Opinion polls, which had the Conservatives 20 points ahead of Labour at the start of the campaign, have closed significantly, and it is all set to be a nail-biting night for the prime minister.

The election is the fourth major poll since 2010 for most people in Britain, with three general elections and the Brexit referendum. In Scotland they had a fifth vote — the independence referendum in 2014.

Ealing Central and Acton

Labour's Rupa Huq has a majority of only 247. That is wafer thin in electoral terms. Huq, whose sister Konnie is a TV presenter and wife of columnist and comedian Charlie Brooker, won the seat in 2015, ousting Angie Bray, a Tory MP who lived in Gloucestershire and was barely seen in the constituency.

Huq, a former university lecturer and expert on suburban culture, is being challenged by American-born Joy Morrissey.

Earlier this week, the Tory candidate was revealed to have had a small role in a saucy movie when she was younger.

Wearing a basque, she rode a man "like a pantomime horse" in the low budget film Geek Mythology, which told the tale of a man's increasingly desperate attempts to have sex.

The Green Party has chosen not to field a candidate in a bid to help Huq and although the Liberal Democrats' have a candidate, local councilor Jon Ball, Lib Dem grandee Vince Cable has been urging voters to vote for Huq.

A significant factor could be Brexit. In the 2016 June referendum, 72 percent voted to Remain and Huq has been playing up her Remain credentials in contrast to Morrissey, who campaigned for Brexit.

It is one of a number of seats across the country where Gina Miller and her Best For Britain group have been campaigning and encouraging Remain voters to vote tactically.

Hartlepool

Hartlepool has been a Labour stronghold for decades, and if they lose it you can be sure it is going to be a long and very depressing night for Jeremy Corbyn.

Again Brexit will be a key factor here. Labour MP Iain Wright — never a big fan of Corbyn — stood down when the snap election was announced and has been replaced by Mike Hill, whose main challenge will come from UKIP.

In 2015 UKIP's Phillip Broughton increased the party's vote by a massive 21 percent, overtaking both the Tories and the Lib Dems and cutting Wright's majority to 3,024.

In 2016 almost 70 percent of the electorate voted to Leave in the referendum, and it will be telling to see whether, after disobeying their party's call to remain, many Labour voters will go one step further and vote for UKIP.

The Conservative candidate Carl Jackson will seek to persuade UKIP voters to switch to the Tories, which could split the anti-Labour vote and work in Hill's favor.

Brighton Kemptown

But they could be undone by strategic voting by a progressive alliance.

In 2010, Caroline Lucas was elected as the Green Party's first British MP in the neighboring seat of Brighton Pavilion.

Although the Greens and Labour are the best of enemies in Brighton — Labour ousted the Greens from control of the city council in 2015 — there are suspicions of a "you scratch our back and we'll scratch yours" deal in which Labour voters switch to the Greens in Pavilion and Greens vote for Labour candidate Lloyd Russell-Moyle.

The Lib Dem vote might also be squeezed by tactical voting and some Tory Remainers might even switch in protest at Theresa May's approach to Brexit.

Dumfries and Galloway

The Conservatives are much more hopeful north of the border, where they think they can surf a wave of unionist sentiment among people opposed to Nicola Sturgeon's demands for a second Scottish referendum.

One seat the Tories hope to win is Dumfries and Galloway, just across the border from England.

In 2015, the SNP's Richard Arkless not only overturned a 695 Labour majority, but overtook the Tories as well to take the seat.

Although it remains a three-way marginal, Arkless is expecting his biggest challenge to come from the Tory candidate, Alister Jack.

The Scottish Conservatives' leader Ruth Davidson is quite popular, despite a rick she made this week when her "Make Britain Great Again" was mocked on social media for its similarities to Donald Trump's "Make America Great Again" slogan.

Dumfries and Galloway is one of a number of rural and largely middle class Scottish seats which the SNP may lose to the Tories. Lord Ashcroft, the former Tory deputy chairman and pollster, has tipped the SNP to lose eight seats overall.

But if Labour's Daniel Goodare were somehow able to win it back it could presage something of a Labour comeback north of the border after Ed Miliband saw his MPs virtually wiped out in 2015.

Gower

Gower is the seat with smallest majority in the entire country. Only 27 votes are in it, so only 14 people changing their minds would mean Labour winning the seat back from the Conservatives.

A Labour victory here, especially a big one, could be a sign of a Labour comeback in Wales.

But if Byron Davies holds onto the seat, and increases his majority, it could indicate that Wales is slipping away from Labour just as Scotland did in 2015.

Gower is a largely rural constituency just to the west of Swansea — a Labour stronghold — and Brexit may play a factor here too.

Although it was split almost down the middle in last year's referendum the Labour candidate, Antonia Antoniazzi, may play on the fears of local farmers who might be concerned by the Tories talk of "no deal" with the European Union, even if that means losing the single market.

Farmers in Gower rely on exports to the EU and would face disaster if they were barred from this market in a hard Brexit world.