Once again, the media is telling us that Ed Miliband’s leadership is in crisis. Labour’s woes in Scotland, allied to continuing poor personal polls has led to another backlash from disenchanted backbenchers and media critics. There are rumours of letters being written and leadership rivals colluding. But is a Labour coup really a serious prospect or is this another media storm?

Undoubtedly Ed Miliband and Labour are going through a difficult period and this is manifesting itself in another wave of anti-Miliband briefing from disaffected elements within the party. But, despite the newspaper headlines, that is all the current situation really is. The media might be getting excited about the handful of letters being circulated by backbenchers, but we should remember that Graham Brady has a whole drawer full of letters calling for David Cameron to resign. Letters on their own do not accomplish anything unless they are part of a popular and coordinated movement against a party leader. So far there are no signs that this is the case within the Labour party.

We must also remember that there is no viable official mechanism for Miliband’s attackers to use in order to force him out. The only mechanism is an official vote of no confidence at a Labour conference, which rules out any official challenge before the election. The alternative is to organise a significant rebellion, with explicit support and sponsorship from senior Shadow Cabinet members, in order to force Miliband to step aside. Again, this does not seem realistic at this stage. There may be rumours of Shadow Cabinet members discussing a post-Miliband world, but that is a world away from supporting an actual coup.

We should remember that traditionally the Labour party is loyal to its leaders. A Labour leader has not been publicly ousted since 1935. Miliband might not be particularly popular with the electorate, but he is generally well liked across the Labour party. Unless there is another serious slide in Labour’s polling figures in the next few weeks, it will be incredibly hard for any anti-Miliband campaign to gain enough momentum and support to force him out.

Indeed, if you examine the state of play across the main parties, and consider the upcoming by-election in Rochester & Strood, then you could note that David Cameron’s long-term security is under more threat than Ed Miliband’s. The polls now in Rochester are consistently dire for the Conservatives and it seems almost certain that UKIP will win this by-election. The margin of that victory will now be crucial for the Conservatives.

If Mark Reckless records a significant margin of victory, which would make his re-election in 2015 much more likely and could potentially inspire a fresh wave of defections, then there could be serious ramifications for Cameron. There is now a sizeable and intractable anti-Cameron bloc of Conservative MPs who are just waiting for the opportunity to challenge his leadership. Under Conservative rules, 46 letters need to be sent to Graham Brady, the chairman of the 1922 Committee, to trigger a formal leadership contest. There are rumours that Brady already has between 10 and 20 letters. A poor result in Rochester could provide the ammunition the anti-Cameron bloc needs to reach the 46 threshold.

This is still an uncertain, and perhaps unlikely scenario. Realistically, David Cameron and Ed Miliband will still both be in place in May 2015. This close to an election it would be a bold and dangerous move to try and replace a party leader. There is a tendency for the media and Westminster commentators to over-hype the significance of these moves and their chances of success. At the moment, both leaders have enough support within their parties to face down any challenges. But given the poor polling of both parties, this is a fraught time for their leadership and they will need to carefully manage party discipline and morale in order to secure their positions.