The opposition Labour party, led by veteran socialist Jeremy Corbyn, has gradually nibbled away at the Conservative lead.
British Prime Minister Theresa May (pictured) was fighting to shore up her general election campaign on Wednesday after a shock projection forecast a hung parliament and left the pound wobbling.
The landslide Conservative victory May hoped to seal by calling a snap election for June 8 seemed much less likely with eight days to go, with the polls narrowing and the premier putting in a lacklustre performance in a major television interview.
The opposition Labour party, led by veteran socialist Jeremy Corbyn, has gradually nibbled away at the Conservative lead in the polls, with the campaign back in full swing after the Manchester terror attack.
But May insisted she had the best plan for taking Britain into negotiations over its exit from the European Union, which start 11 days after the election.
"The only poll that matters is the one that's going to take place on June 8," she said on a campaign visit to Plymouth in southwest England.
"Then people will have a choice as to who they want to see as leader, who they want to see as prime minister taking this country forward in the future: me or Jeremy Corbyn.
"I have the plan for the Brexit negotiations but I've also got a plan to build a stronger and more prosperous Britain and I'm confident we can do that."
May called the election three years early in a bid to strengthen her slender majority in parliament going into the Brexit talks.
The decision was made on the back of polls that at times put the Conservatives 20 points ahead and on course for an overwhelming victory.
But opinion polls have showed the gap between the Conservatives and Labour closing.
"The movement in the polls over this campaign is bigger than in any election I've covered since 1945," veteran poll watcher David Butler said on Twitter.
The Daily Telegraph newspaper's rolling average of the last eight polls now puts the Conservatives on 44 percent, Labour on 36 percent, the centrist Liberal Democrats on eight percent and the anti-EU UK Independence Party on five percent.
A shock new projection on the front page of The Times newspaper forecast a hung parliament in which the Conservatives would fall short of the 326 seats needed for a majority.
Using new constituency-by-constituency modelling, the projection by pollsters YouGov said the Conservatives would lose 20 seats to 310, with Labour up 28 to 257.
The model was based on 50,000 interviews over one week.
However, it has a very wide margin of error, saying the Conservatives could get anywhere between 274 and 345 seats meaning they could also increase their majority.
Pound takes a hit
The British currency was hit in Tuesday overnight trading, dipping by as much as 0.5 percent on the back of the YouGov poll.
It recovered ground early Wednesday, trading broadly flat at 1.28 against the dollar and up 0.1 percent against the euro at 1.14.
Sterling had risen in recent weeks on the prospect that the Conservatives would win by a landslide.
"There is a slightly more cautious attitude as a result of those narrowing polls," said Michael Hewson, chief market analyst at CMC Markets.
Sensing the momentum, Corbyn tried to shift the debate away from Brexit on Wednesday by going on the attack on public services, traditionally one of Labour's strong cards.
He warned that schools and state healthcare in England would be put at risk if May remains in office.