IT could be one of the biggest events in modern political history – and it will go on for days.

The general election on May 7 will coincide with council elections across much of Dorset, meaning the poll will be followed by more than two days of counting.

And if the opinion polls are to be believed, it could take days before Britain knows what its next government will look like.

None of the surveys have suggested an overall majority for either of the main parties – and negotiations in the event of a hung parliament could involve not only the Liberal Democrats but the Scottish Nationalists, UKIP and the Green Party.

Voters in Poole, Bournemouth, Christchurch, East and North Dorset and Purbeck will all elect district or borough councillors at the same time as they elect their Westminster representative.

And in many rural areas, there will be elections to town or parish councils as well.

All that makes it the biggest counting job that local authorities have taken on for at least a generation.

General election results are expected in the early hours of Friday morning, but the local government counts will not take place until Friday in Bournemouth and Poole – and Saturday for Christchurch, East Dorset and North Dorset.

Dorset’s most closely fought general election result in 2010 was in Mid-Dorset and North Poole, where Liberal Democrat Annette Brooke saw off a challenge from the Conservatives to hold her seat by just 269 votes.

With Mrs Brooke retiring and Nick Clegg’s party performing weakly in the opinion polls, her successor Vikki Slade will have her work cut out to hold the seat against the Tories.

Meanwhile, Labour’s sights will be set on South Dorset, which they lost to Conservative Richard Drax at the last election.

Mr Drax came away with a hefty majority of 7,443 in 2010, but Labour’s Jim Knight had served two terms before that, and the party will be hoping its candidate Simon Bowkett can challenge the Tories.

Christchurch MP Chris Chope has one of the most comfortable Tory majorities in the country – 27,888 over the Liberal Democrats – although the strong presence of UKIP in the constituency could skew the result.

New Forest West’s Conservative MP Desmond Swayne also enjoyed an enviable majority, of 16,896.

The effect of the UKIP vote in the traditionally true blue constituencies of Bournemouth East, Bournemouth West, Poole and North Dorset is unclear as well.

Meanwhile, North Dorset is certain to have a new MP following Conservative Robert Walter’s recent announcement that he would be standing down.