Can The Leaders Survive The Election Fallout?

It is the election that no leader can win - even if they do win.

David Cameron, Ed Miliband, Nick Clegg and Nigel Farage could all be wondering if they will have a job when the dust settles on the General Election.

Here's the verdict on how the leaders have performed over the last five years and what their chances are of surviving until 2020.

:: Nick Clegg

There is an argument about Nick Clegg's time in coalition that runs along the lines that he is the politician who has achieved the most, with the least power. It's the very thing that has made him so unpopular.

To get what he wanted, he has had to make some significant sacrifices, from which he will never recover. Actually it's mainly just the one but it will be his political epitaph: "student tuition fees U-turn".

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That said, the Tories will be reluctant to let him go. They need Mr Clegg if they want a Lib Dem coalition.

There have been rumblings that senior party members have no wish to reprise the 2010 deal. The parties are more ideologically opposed than five years ago.

Labour, however, would arguably rather deal with Vince Cable, who has held the coalition at arms' length/missed very few opportunities to criticise his Conservative colleagues.

Former party chairman Tim Farron has also been mentioned as potential next leader.

Although Mr Clegg says he has the energy to continue as Lib Dem leader, there's no getting away from the fact he has presided over a crash in party support - even if the Lib Dems perform considerably better than has been predicted.

And, of course, despite Tory efforts to save him, winning back his Sheffield Hallam seat is far from a sure thing.

If the Lib Dems are to rebuild as a significant force for 2020, Mr Clegg will have to go and there's a feeling that if the party is not needed for a coalition or he loses his seat that could be sooner rather than later.

:: David Cameron

David Cameron has not helped himself by firing his own Tory leadership race gun - and then listing his possible successors.

He said he would serve no more than two terms and it remains to be seen if he will even make the second much less last the full five years if he does.

Arguably at the very least, any Conservative leader who fails to win a significant majority against one of the most unpopular Labour leaders of all time when the party is likely to be wiped out in Scotland has "questions to answer". Candy from a baby and all.

Some Tory donors have expressed misgivings about the way Mr Cameron has conducted himself during the six-week campaign despite "pumped up" Dave making an appearance with shirt sleeves suitably rolled up in the later stages.

If the Conservatives fail to form the next government expect a fairly swift leadership contest.

Boris Johnson, Theresa May and George Osborne are all in the frame, although whether they would be reasonable propositions for 2020 is up for debate.

If the party does scrape together a coalition, Mr Cameron may still face a challenge for all the reasons above.

In any event he is unlikely to serve the full five years because the Tories will want someone new at the helm ready to tackle the 2020 vote.

:: Nigel Farage

Despite his attempts to thrust others into the limelight, Nigel Farage is still UKIP and UKIP is still Nigel Farage.

His success as leader was phenomenal right up to November last year, when this party started to look like a spent force.

Sure he delivered the "earthquake" promised in the local and European elections, and he has seen two MPs win seats in by-elections but there is an argument he has failed to capitalise.

And the party is still afflicted by candidates who choose to express themselves in ways considered homophobic, sexist, threatening, or all three.

There are also doubts that Mr Farage will win South Thanet despite focussing virtually all his campaign attentions on the seat.

He has previously said if he failed to win the seat he would have to reconsider his leadership - but in those interviews he always worked on the assumption there was no chance of him losing.

Then there have been concerns about his health - he admits he did too much in the early days of the election campaign and has been on medication for back problems caused by the airplane crash he was in on polling day in 2010.

If UKIP is to prove itself as a party it will need to be able to continue to muster significant support under another leader.

Douglas Carswell, the former Conservative who became UKIP's first MP, has to be in the frame, as does Suzanne Evans, who drew up the party's manifesto. The party deputy Paul Nuttall is also likely to be in the running.

:: Ed Miliband

In his favour, the Labour leader hasn't been the election campaign car crash the Conservatives were expecting.

His performance, which has seen an astonishing reversal of his dismal popularity poll ratings, has surprised many - particularly as he was coming from such a low base.

But six weeks of good performances cannot make up for five years of bad polls. In November an Ipsos/Mori poll named him the most unpopular Labour leader ever among the party's own supporters.

His entire time at the top has been blighted by suggestions of imminent leadership challenges and the consistent drip, dripping of commentary insisting his brother, David, would have done a better job.

Under his tenure Labour has seen its support in Scotland all but wiped out but at every stage - a referendum on independence and an election campaign - he has failed to tackle the soaring SNP.

In the last six weeks he has spent his time ruling out coalitions with Nicola Sturgeon but he has not tackled her on the party's performance on NHS targets in Scotland or the plummeting oil revenue forecasts which undermine the case for independence it outlined before September's referendum.

One can only assume this is so he can blame any considerable Labour losses on the Scottish Labour leader Jim Murphy.

What makes Mr Miliband's position safer than the other leaders is the paucity of likely successors.

Yvette Cooper is arguably the only one ready to make the step up but it is starting to feel like her window of opportunity is closing - the same goes for Andy Burnham.

Chuka Umunna and Rachel Reeves feel like they need more time.

In the event of a loss it might mean Mr Miliband will stick around for a while before the party is ready to rebrand at the top. (There is talk brother David has an eye on returning from the US to lead Labour into 2020.)

And if he wins then he will likely stay at the top at lot longer - although it may not be safe to put money on him staying the course for the full five years.