Perhaps the only safe prediction about the general election is that it will result in another hung parliament. For the Liberal Democrats, as potential coalition partners, the question arises of whether they will side with the party that wins the most votes or the one which wins the most seats. As in 1951 and February 1974, they may not be the same. Labour's better-concentrated vote (and the unreformed constituency boundaries) mean that is likely to win more seats if the parties are tied or even if the Tories are slightly ahead.

To date, senior Lib Dems such as Nick Clegg and Danny Alexander have simply dodged the question (though both privately favour the Tories). But in an interview with me at the launch of his re-election campaign yesterday, Tim Farron, the party's left-leaning former president and the frontrunner to be its next leader, revealed that he believes the Lib Dems will have to support whichever party wins the most seats (with Labour the obvious choice). Speaking in his constituency of Westmorland and Lonsdale, where he was introduced by Shirley Williams, he told me:

Let’s say the Tories get more votes and Labour win more seats, which is quite possible, we may think that morally we should put the Tories in but they won’t have enough seats, we won’t have a choice. Last time round, us plus Labour was 11 short of a majority of one, so a majority where we’d have had to rely on Jeremy Corbyn voting through the Budget, things like that, for instance, so 11 short even of that level of a majority, so it wasn’t an option.

He added: "I think the same thing will be the case this time round, almost certainly. We will not have a choice. We will be presented with an arithmetic by the electorate and all parties must be grown up enough to accept it and not say, ‘well, thank you for your opinions, we didn’t like it, tough’. Whatever the electorate give us through this fruit machine of an electoral system that we have, we have to be big enough, grown-up enough to make sure it works.

"The fundamental promise we must make to the electorate is that we will respect the outcome of the electorate and we will ensure, do everything in our power to ensure, stable government straight after the election, whether we are part of it or not."

While the Lib Dems are likely to maintain their ambiguous stance, it is significant that Farron, who will be a key player in the post-election period (and could even take over as leader if Clegg loses his seat or resigns, has made his view clear.

When I asked him whether he would stand for the leadership the next time there was a vacancy, he sensibly replied:

My answer to that, and I know why you ask it, if I answer that, obviously a whole bunch of things happen, one way or the other. My take is that this is, and you know there’s no kind of hyperbole here whatsoever, the toughest election we’ve faced, certainly for a generation, possibly longer. In which case, me giving headspace or column space, to any ambition I may or may not have, whatever happens after 8 May, would just be energy-sapping, it would be diverting, it would be arrogant. I’d be a bit of a prat if I spent much time or any time thinking about it.

The full interview with Tim Farron will be published next week.