By CGTN's John Metherell‍

Opinion polls suggested that UK Prime Minister Theresa May might win by a landslide when she called for Thursday's general election in the UK. But those polls narrowed during the campaign and there is a possibility that no party will win a majority.

When Theresa May called her surprise snap election, she said all about Brexit. But that was before the latest deadly terrorist attack. 

With security now a central focus of the campaign, Theresa May's past record is under scrutiny. And on Monday, there were calls for her to resign. 

Critics point out that while May served as Home Secretary for six years, the number of police officers in England and Wales fell by almost 20, 000.

When she called the election, May was 25 points ahead in the opinion polls. She said giving her an increased Parliamentary majority would strengthen Britain's Brexit negotiating position.

For May, it appeared an electoral walk in the Park and pollsters anticipated a landslide. The Party of the Left leaning Labour opposition leader Jeremy Corbyn was in disarray. May, by contrast, is her Party's big selling point. Her message repeated mantra-like at every stop.

Then something happened. European Union leaders in Brussels, bemused at a General Election called on the eve of critical talks, said the outcome would have no bearing on Brexit negotiations. Relations ahead of the talks deteriorated badly.

Threats, said May, deliberately timed to affect the outcome of the General Election. 

Meanwhile, Jeremy Corbyn was proving an effective campaigner. The veteran Labour politician's self-deprecating style winning over voters.

One of Britain's leading polling companies says the difference now lies within the margin of error.

So, from dreaming of a Parliamentary majority in three figures at the outset of the campaign, she's now fighting for every vote.