U.K. Prime Minister Theresa May would only have herself to blame if an awful election campaign results in embarrassment, political analysts have told CNBC.
While a vast majority of observers still expect May to emerge victorious on Thursday, a Survation poll published last weekend placed the prime minister's ruling right-wing Conservative Party ahead by just a single percentage point. This has forced investors to consider a vast range of possible election outcomes.
"May's reputation at the start of the campaign was high. Her ruling Conservative Party enjoyed a lead of more than 20 percentage points over the opposition Labour Party. Calling an election appeared to be a masterstroke," said Mujtaba Rahman, the Europe director of the Eurasia Group, a political risk consultancy.
"(However), her presidential campaign means that May has no one to blame but herself," Rahman added.
When May "reluctantly " called the June 8 snap election seven weeks ago, the Conservatives boasted a seemingly unassailable lead over the left-wing Labour. However, Labour leader Jeremy Corbyn has since soared into contention, putting May's election gamble in doubt with just two days to go.
May has come under intense scrutiny over security concerns in the wake of the London Bridge attacks at the weekend, in which seven people died. Corbyn argued that May had "presided" over significant cuts to police numbers over the past seven years and as a result, he backed calls for the prime minister to resign on Monday.
While May has since defended her record on security during her time as Home secretary, a former key advisor to David Cameron, Steve Hilton, has urged the Conservative leader to step down with less than 72 hours before the vote.
Kallum Pickering, senior U.K. economist at Berenberg, predicted that while the Conservatives still have a 65 percent chance of winning the election, it now appears more likely than not that May would be "embarrassed" by the result.
"Of the 65 percent probability we put on a Conservative win, we see a 30 percent chance they win with a lower majority, a 25 percent chance of a hung parliament and a 10 percent chance of a Labour majority," Pickering said in an email to CNBC.
Britain's prime minister called the election, despite repeatedly saying she would not do so, in an attempt to secure a strong mandate during Brexit negotiations and, presumably, to increase the 17-seat lead that she has in the House of Commons.
In the event of a hung parliament, in which no party would have a clear majority, the U.K. would be thrown into a political deadlock with less than two weeks before formal Brexit talks are due to begin on June 19.
"She didn't need to (call the election), and it looks now as though she has been faulty in her judgment and that's something which will count against her in the polls," David Marsh, managing director and co-founder at OMFIF, told CNBC on Monday.
The decline in support for the Conservatives has coincided with an unexpectedly strong performance from Corbyn and a surprise announcement by May in which she suggested elderly voters would need to pay more for social care.
"A Tory manifesto with no 'good news', unlike Labour's long, popular if expensive shopping list, and a better-than-expected campaign performance by Corbyn, allowed Labour to close the gap in the opinion polls, albeit from a low base," Eurasia's Rahman said.
The prime minister later backtracked over the social care plans, which critics labeled the "dementia tax ", as support deteriorated among wealthy homeowners. The upset caused among a core source of support for the Conservatives appeared to prompt May's political U-turn, although she has repeatedly insisted "nothing has changed."
Conservative candidates told the Huffington Post last week the party deserved to lose the election given the way the party's campaign had been negotiated to date. One Conservative candidate, which the media outlet did not name, said they were pretty "f-----d off" with the prime minister for shattering confidence in the parliamentary party.
"Jeremy Corbyn is running a good campaign but beyond anything else, he's a beneficiary of a truly awful Conservative campaign," Tom Baldwin, former director of communications to ex-Labour leader Ed Miliband, told BBC Newsnight last week.
"I've never seen anything like it — the prime minister is disintegrating in front of the public, she's gone from basing her entire campaign around her personality to her brand being junked within three weeks," Baldwin added.
Pollsters have projected a vast range of outcomes for Thursday's vote, ranging from a landslide majority of well over 100 seats to a YouGov prediction that forecast May would win with 305 seats, slightly less than the 326 seats required for a majority in the 650-seat parliament.
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