Here’s a question. If a party has an MP and commands a sizeable share of the vote, surely its leader should be given a seat at the table in the pre-election debates?

As it happens, the major broadcasters agree – to an extent. In March, Ofcom ruled that UKIP should be treated as a major party (in the context of the European elections), and following Douglas Carswell’s election as the first UKIP MP last Thursday, the BBC, ITV, Sky and Channel 4 announced that the party’s normally shy and retiring leader would be pitted against David Cameron, Ed Miliband and Nick Clegg.

There will be three debates in total, one a head-to-head between Miliband and Cameron – a decision that some have noted is at odds with the fact that we do not have a presidential system – and another between the three of them.

Given that UKIP are climbing in the polls – and even tipped to achieve as many as 30 seats in the next general election – it’s not a stretch to argue that Farage should have a say. What is contentious is the decision to include him, but exclude the leaders of other parties with the same number of MPs, namely, the Green Party.

As soon as news emerged of the debate format, commentators started questioning the logic of leaving out Natalie Bennett, given that the Green Party has had a voice at Westminster since the election of Caroline Lucas in 2010 and has been polling at up to 7% –  a similar level to the Lib Dems.

‘It could only be more traditional if it was hosted in the Great British Bake-Off tent,’ observed Willard Foxton. ‘Democracy is about hearing from everyone, not just from the two men most likely to be Prime Minister,’ said Chief Executive of the Electoral Reform Society, Katie Ghose. ‘The debates should be an opportunity to hear from the leaders of all parties which command a significant amount of support.’

‘Out of touch… with the public mood’, was Bennett’s verdict on her exclusion, a comment echoed by Plaid Cymru’s leader Leanne Wood. The SNP’s Angus Robertson added that it ‘clearly wrong that the leader of the third biggest political party in the UK should be shut out of these network debates’.

Fewer argued that George Galloway should be involved, but the Respect leader and the party’s only MP himself tweeted: ‘I am ready to join Caroline Lucas MP in a legal challenge against our exclusion from the leaders debates in the forthcoming general election’.

For Farage, it’s a good result, even if he would only concede that ‘the decision is better than it could have been’, grumbling about being left out of the other two. ‘If the political landscape continues to change we would expect and ask for inclusion in a second debate.’

But there is a suggestion that the broadcasters will have to amend their plans, which are, at this stage, merely that. A petition challenging them has attracted 2.500 signatures, but more significantly the Lib Dems have made clear they are unwilling to accept the proposals and plan to challenge them. ‘We do not accept the proposal that the Liberal Democrats, as a party of government, should be prevented from defending our record,’ they said. ‘That is the case we will make strongly in the negotiations that will now take place.’

Meanwhile, the SNP have indicated that they may well repeat their action in 2010, when Alex Salmond mounted a legal challenge over his exclusion from the debates.

Cameron is likely to agree that the proposals need a rethink. Asked whether Bennett should be given a slot, he agreed that he could not see ‘how you can have one party in it that has an MP in Parliament and not another party’ with the same representation’. Miliband, meanwhile, has suggested he is perfectly content with the format being proposed.

For Cameron, and perhaps also Miliband and Clegg, the threat of a vote-winning performance from Farage at a pre-election debate is very real. After all, the refrain of ‘I agree with Nick’ was said to have helped the Lib Dems’ performance in 2010, so Cameron may well be keen to avoid Nigel stealing the show this time round. With Bennett on the panel, Farage would have less opportunity to pose as the only ‘none-of-the-above’ option.

‘He is terrified of debating with Nigel Farage’, concluded the Indy’s political commentator Matthew Norman. Others, including George Eaton, have suggested Cameron’s righteous indignation is part of a bid to torpedo the debates entirely.

If so, he is unlikely to succeed. While the broadcasters may be compelled to amend their plans, there seems to be sufficient appetite for the televised debates. Which means that, come next spring, we may well be hearing cries of ‘I agree with Nigel’ coming from our screens.