Here's why people are blaming UK leader Theresa May for her sliding election polls

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.

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.

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.

Source: Bloomberg Pro Terminal

Jr Trader Alexander Kumanov

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