COULD we in Sussex be experiencing the first tremors in what might become a national political earthquake?

This week we’ve seen announcements from the Liberal Democrats saying they’re not going to fight the Green Party’s Caroline Lucas in Brighton Pavilion on June 8 and the Greens’ Davy Jones, who fought Kemptown in 2015, saying he’ll stand down to increase the chances of Labour taking that seat from Conservative Simon Kirby.

So, is Labour part of this “Progressive Alliance”?

Council leader Warren Morgan has already dismissed any deal with the Greens and he’s been backed by his council colleague Caroline Penn who said recently: “A progressive alliance is just a dodgy backroom deal where Greens demand everything and give up nothing.”

But this is not the whole story. Labour’s David Arnold – who masterminded the party’s campaign in Kemptown in 2010 and 2015 – has come out in favour of an alliance, arguing that if the Greens also stand aside in Hove (where Labour’s Peter Kyle is defending a small majority) then Labour should not contest Pavilion.

Greg Hadfield who leads Momentum in Brighton, the left-wing pressure group that supports Jeremy Corbyn, has also tried to get in on the act by urging Labour supporters in Pavilion not to campaign there but to work for the Party in Kemptown.

Sounds like he’s joined the Alliance by urging Labour members not to oppose Caroline Lucas, but more cynically he is trying to divert Labour support from Peter Kyle in Hove– who has made no secret of his lack of enthusiasm for Jeremy Corbyn.

In other words, Hadfield and his supporters in Momentum appear to be going all out to see the Conservative defeated in Kemptown but are clearly relaxed about the Tories defeating Peter Kyle in Hove. Cynical? Just a bit.

And let’s not forget these calls for tactical voting are not just happening on the left. Ukip has announced that they will not be running candidates against those Conservative MPs whom they regard as sufficiently “hard Brexiteers”.

But aren’t these sort of deals a bit undemocratic – denying voters the opportunity of voting for the party of their choice?

In theory, yes but in practice the current first past the post electoral system is equally anti-democratic, depriving voters in many seats of any meaningful vote.

For example, in Brighton is there any point in voting Liberal Democrat anywhere when the party has no chance of winning any seats?

But if Lib Dem supporters vote tactically, against the party they don’t want to win, then their “wasted” vote has some meaning.

And there’s another issue, perhaps even more important.

This potential political earthquake isn’t just about tactical voting. As David Arnold says in his open letter: “The electorate in our city don’t fit neatly into the boxes that we, as party activists, construct for them.”

This is true not just in Brighton but nationally too.

The old party boxes are beginning to creak as new dividing lines come to the fore. In this election, and perhaps beyond, that new divide is between Remain and Leave supporters.

Leave voters will want to strengthen the Prime Minister’s hands in her negotiations with the EU.

Remain voters will want to ensure that, at the very least, the UK remains in the single market, (or as near as possible) but more than that, most would want the final package to be put to the electorate as whole in a second referendum.

But hold on, I hear you say, we’ve already decided by 52 per cent to 48 per cent to leave. Ah yes, but that was then, this is now.

Since the referendum, the polling organisation YouGov has been asking the public “In hindsight was Britain right or wrong to vote to leave the EU” and every month their poll has shown a majority saying it was right.

Every month that is until now, for their latest poll shows that, for the first time, more people think it was wrong than right to leave the EU.

It’s only one poll and we know how wrong polls can be but still this feels like another tremor that could be heralding a quake.

Whether that quake is strong enough to mean that Mrs May’s election gamble has failed still seems unlikely in the extreme, but then whoever thought that Donald Trump would be currently sitting in the White House, or for that matter, we’d be heading out of Europe?

In this age of uncertainty anything can happen.

Ivor Gaber is Professor of Journalism at the University of Sussex and is a former political correspondent at Westminster