They will be the biggest test of electoral opinion since 2017 as voters head for the polls in May to decide who they want to run local services for the next four years.

But they are taking place in the shadow of Brexit and one of the most turbulent and unpredictable political backdrops in years. Elections are being held in every council - with the exception of Kent County Council - with most having "all out" polls in which every ward is up for grabs.

Political editor Paul Francis assesses how the parties may fare in the battle for more than 500 wards across the county.

CONSERVATIVES: The electoral map of Kent has been dominated by a distinct shade of Tory blue, with the party in control of all but one authority.

The question of whether it can command the support it needs to retain its grip will be tested in the face of barely-disguised disillusionment among party members and activists over Brexit. Candidates are not getting the warmest of receptions on the doorstep but not because voters are disapproving of the way the council runs services.

Support is said by some to be evaporating after Theresa May’s decision to open talks with Jeremy Corbyn. Having said that, it ought not to be troubled in its west Kent heartland, with Sevenoaks and Tonbridge and Malling pretty safe bets given the hefty majorities the party has.

On paper, Tunbridge Wells, where a third of seats are being contested, should be safe too but the independent group known as the Tunbridge Wells Alliance could spring a surprise or two. Elsewhere, a split in the Conservative group in Gravesham may make the party vulnerable to Labour.

And Swale could be one to watch if a coalition of rival parties muster enough support to deprive the Conservatives of outright control.

As to the decline of Ukip as a political force in the county, it could cut both ways. On the one hand, it removes the potential of supporters switching; on the other hand, Conservative voters may - in the absence of a Ukip candidate - choose to stay at home.

LABOUR: The party is optimistic about making gains at the expense of the Conservatives but whether those gains will be enough to take outright control of councils is another question. It is contesting elections from a low base: its numbers in eight authorities is in single figures and it has no councillors at all in two.

And like the Conservatives, the party has its own divisions over Brexit. Many activists share the same disdain for the party's willingness to take part in talks with the Conservatives over a compromise deal. Nevertheless, it has its eye on some councils where it believes there is a chance of taking power. Medway is an obvious target, but overhauling the Conservative majority represents a challenge despite a shock by-election win last year in the ward that had been represented by MP KellyTolhurst and Ukip - despite its support nationally plummeting - is contesting 23 wards.

Dover, where it currently has 15 councillors against the Conservatives with 24, may present an opportunity but arguably its best prospect is Gravesham where the Conservative group split last year. Interestingly, Ukip is fielding 14 candidates here, showing the party is not quite a spent force.

Despite returning Labour’s only MP in 2017, it may be too much to expect the party to oust the Conservatives in Canterbury, where it currently has four councillors against 28.

LIBERAL DEMOCRATS: While the party has maintained a solid core in the County Town of Maidstone, where it runs a minority administration, it is a case of rebuilding from a low base elsewhere. Currently, there are seven councils with no Liberal Democrat members at all; in others, it is in single figures.

However, there have been some encouraging glimmers of hope and in two councils - Folkestone and Hythe and Canterbury, the party has a struck a non-aggression pact with the Green party to enhance its prospects in a selection of targeted wards where their vote might traditionally have split.

There is optimism that it could do well in Faversham - which could be a factor in Swale - but overall, this could be an election that marks a staging post for the party rather than one in which it springs any great shocks.

GREEN PARTY: The party made a key breakthrough in the county in 2013 when it returned its first county councillor, Martin Whybrow who represents Hythe West, Folkestone. Since that time, however, it has not seen any further successes but is fielding candidates in most areas. Its election pact with the Liberal Democrats in Folkestone and Hythe and in Canterbury could help tilt the balance. Each party has agreed that, in certain wards where the other party has more chance of gaining votes, they will not stand a candidate, or only one candidate in a three-seat ward.

UKIP: The party that made Kent something of a stronghold under Nigel Farage did so on the back of successes in council elections but splits, defections and acrimonious in-fighting over the party’s leadership has seen it decline as a political force. It lost control of Thanet council last year - the only authority it has run - and is fielding just two candidates there. In Swale, where it returned nine councillors in the 2015 election, there is a similar picture: just two candidates are standing and those that were elected as Ukip councillors have reformed as The Swale Group, focusing on campaigning over housing development.

However, Brexit makes it too early to write the party off. In some councils, there is a healthy number of candidates. In Medway, 23 candidates are standing; in Dartford, it is contesting 16 wards and in Gravesham, 14.

INDEPENDENTS: Voter antipathy to the mainstream political parties make council elections potentially fertile territory for independent groups. In Tunbridge Wells, the Tunbridge Wells Alliance came about as a result of controversy over the council’s plans for a £90m civic centre complex and theatre at Calverley Square. It is fielding six candidates in the 16 wards being contested. In Dartford, the already well-established Swanscombe and Greenhithe Residents Association is fielding 19 candidates.

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