The debate about Nick Clegg's political future has been raging in the run up to polling day.
Polling by Lord Ashcroft has been predicting that Labour's Oliver Coppard may oust Nick Clegg and take a seat that has historically been held by the Conservative or Liberal Democrat Parties.
This would pose huge problems. The Liberal Democrats would loose their leader and the Deputy Prime Minister - as he would remain until a new government was formed - wouldn't have a seat.
So, will Clegg loose his seat?
Ashcroft's April polling recorded Labour at 37% of the vote and the Lib Dems at 36%, so things are close.
But, for a number of reasons I'm not so sure that Labour will secure victory.
First, we know that we need to be cautious about polling around high profile figures. People are, unsurprisingly, unwilling to voice support for unpopular politicians and Clegg's poll ratings have been abysmal.
57% of people are dissatisfied with the way Nick Clegg is doing his job according to IPSOS MORI polling. And even amongst Lib Dem supporters only 56% are satisfied. So, people are unlikely to be falling over themselves to express their support for Clegg,
Second, Clegg is sitting on a huge majority. He won in 2010 with 53% of the vote - getting 29.9% more of the vote than the Conservatives. What is significant here is that Labour - the party now threatening the Tories - were in third place and so have a huge hill to climb to gain a majority.
Clegg polled 27,324 votes whilst Labour got 8,228. That is a gap of 19,096 - a huge number of votes to turn around.
We know from academic research that local campaigning can make a huge difference in these kinds of situations but the national Labour Party have not been pouring resources into the seat.
The local candidate, Oliver Coppard, has been running a very active campaign but the local Labour Party is relatively small and lacks experienced activists and established campaigning procedures - the key ingredients for delivering success in local campaigns.
It is for these reasons that I've been cautious about the Ashcroft polls and have predicted that Clegg is likely to hang on to his seat.
However, reports are coming in that turnout in Sheffield Hallam is incredibly high - potentially even higher than in 2010. What this means for the outcome of the seat is difficult to tell - could it be a huge anti-Clegg vote, and will that vote go to Labour? It's going to be an interesting few hours until we find out.
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