The UK Independence Party (UKIP) is hoping to build on its shock byelection victories in Clacton and Rochester & Strood by stealing more seats from the mainstream Westminster parties at next year’s General Election.

Current forecasts have them gaining between 9-14% of the national vote, although the distribution of those votes could see them pick up only three or four seats. Even then, doubling their current representation in Parliament would be seen as a major coup for UKIP leader Nigel Farage.

Given the collapse in Lib Dem support in the polls, Labour or the Tories may well require more than one coalition partner to secure a Commons majority. This could leave UKIP as a possible kingmaker — a prospect that Farage relishes.

These are UKIP’s top targets for May as revealed by the party’s own polling.

1. South Thanet

Farage was selected by UKIP members to stand in the Conservative-held constituency in east Kent. Announcing his intention to stand in a column for The Independent Farage expressed his confidence in taking yet another seat from the Tories:

“Of course I think I stand a good chance of winning. I have fought the seat before and it is in my home county of Kent and an area I have represented in the European Parliament since 1999.”

His confidence aside, it is unlikely to prove an easy ride for the bombastic UKIP leader. In 2010 the Conservatives won 48% of the vote, a 7.4% swing from second-place Labour, while UKIP garnered only 5.5%. However, Farage’s party stormed home in last year’s local elections and a recent poll by Survation at the end of November had UKIP at 30%, only 5 percentage points behind Labour with the incumbent Conservative candidate pushed into third place.

Verdict: Farage may still be trailing in the polls but his national profile may just be enough to overcome that deficit. Highly possible.

2. North Thanet

The neighbouring constituency of North Thanet is also high on the UKIP hit list. Back in 2010 it was also comfortably won by the Conservatives, with MP Roger Gale taking 52.7% of the vote — a margin of victory of over 30 percentage points from Labour. UKIP took a meagre 6.5%.

Time, however, has not been a friend of Mr Gale. In a local poll taken at the end of September his lead had narrowed by under 2%, with UKIP surging to 31.5% against the Conservatives 33.4%.

With momentum looking to be with the party after its byelection victories UKIP’s candidate, barrister Piers Wauchope, is confident that such a narrow lead can be overturned. Wauchope previously lost out to Farage in a bid to become UKIP candidate for South Thanet.

Verdict: Right on the doorstep of Farage’s campaign, Wauchope is likely to benefit from the media attention and popularity of his party leader. Highly possible.

3. Boston and Skegness

Since the constituency of Boston and Skegness, on northern shore of The Wash, was formed in 1997 it has been solidly Conservative. However, it is also the seat that saw one of the best UKIP performances at the 2010 election with the party taking 9.5% of the vote.

According to a Survation study that extrapolated from the May 2013 local election results, if they were repeated next May it would also give UKIP it’s largest margin of victory (11.18%). As a column from last year on Conservative Home put it:

“Anyway I suppose if they are to get an MP at the next election then Boston and Skegness is their best bet.”

However, the author swiftly dismissed these concerns adding that “personally I doubt we will get any UKIP MPs”. Well, they already have two at least one of which (Clacton) they are all but certain to hold next May. So if a wise man today wouldn’t bet against UKIP having at least one MP, what’s to stop the party adding to its tally?

A Survation poll arranged by UKIP in September gave the party a comfortable lead of 46% to 26% for the Tories. This race is certainly going to be an interesting one.

Verdict: This looks to be UKIP’s best shot of adding to its seats. Highly possible.

4. Thurrock

The constituency of Thurrock was held by Labour at each General Election from 1945-2005 barring a single loss to the Conservatives in 1987. However, it was taken off them by a resurgent Tory party in 2010 as MP Jackie Doyle-Price managed to sneak over the line by a mere 82 votes.

It is among the must-win seats listed by the Labour leadership if the party is to have any chance of returning with a majority of seats next year. There’s only one problem — UKIP is leading in the polls.

A poll by Lord Ashcroft in June showed UKIP on 37% compared to Labour’s 29%. If this result is realised next May it would be a hammer blow to Labour leader Ed Miliband’s dream of a majority and send some worrying messages to his party’s strategists. As Jim Pickard put it in the Financial Times:

“It used to be a working assumption that a strong showing for Ukip would damage the Tories. But the party’s anti-immigration, anti-EU message is rapidly picking up supporters in one-time Labour heartlands.”

Verdict: Signs have been looking good for UKIP in Thurrock, although a win is far from guaranteed. What can certainly said is that this seat will be one to watch to gauge whether the party has been able to turn its surge in the polls into parliamentary gains. Highly possible.

5. Great Yarmouth

Another Conservative-held coastal constituency that is very much the heartland of UKIP. The seat has bounced between Labour and the Conservatives with the latter losing out in the 1997 General Election before winning it back in 2010.

The result, however, was far from overwhelming with the Conservatives taking 43.1% to Labour’s 33.2%. UKIP took 4.8%.

Even more worrying for MP Brandon Lewis, who is also the Minister of State for Planning & Housing, is that UKIP’s poll figures have taken huge chunks out of his lead. A poll by Lord Ashcroft of the constituency in July had UKIP on 32% to the Conservatives’ 33% — and that was before the parties byelection victories over the past few months.

Unfortunately, for UKIP to take advantage of its surging poll numbers it will have to avoid getting in its own way. And on this score things don’t look so positive. In July Matthew Smith, the party’s parliamentary candidate for Great Yarmouth, stepped down in order to fight charges of electoral fraud.

Last month Alan Grey, a local businessman and County Councillor for Breydon, was picked to replace Smith but clearly the party’s progress in the local area has been set back by events of recent months. It remains to be seen how much damage it has inflicted on its chances.

Verdict: Great Yarmouth was looking a much better prospect for UKIP earlier in the year. If its support holds up this remains a winnable seat, but that’s now a very big “if”. Possible but unlikely.

6. Eastleigh

The Eastleigh byelection last year provided an early glimpse of the shock that UKIP was above to give the Westminster establishment with the party beating both the Conservatives and Labour into second place behind the Liberal Democrats.

UKIP’s Diane James took 11,571 votes or a 27.8% share in a seat that the Tory leadership had earmarked as a key target for next May. This put her only marginally behind the victorious Lib Dem candidate Mike Thornton on 32.1%.

The Conservatives had hoped that Prime Minister David Cameron’s pledge to hold and in/out referendum on the UK’s membership of the European Union would be sufficient to blunt UKIP’s popularity. Eastleigh helped to demonstrate the folly of this strategy.

There was better news for Cameron from recent polls, however. A Lord Ashcroft poll from August had the Tories leading on 32% with UKIP still stuck behind the Lib Dems in third place.

Verdict: The byelection may have been UKIP’s best hope of winning Eastleigh, at least for the time being. With the party currently sitting in third place this one looks set to remain just out of Farage’s grasp. Unlikely.

7. Forest of Dean

Once again the Forest of Dean in the western part of the county of Gloucestershire was a comfortable Tory hold in 2010. Mark Harper held the seat for his party with a 9.2% swing from Labour to the Conservatives, delivering him 46.9% of the vote to UKIP’s 5.2%.

Despite this, the analysis of local election results in the constituency by Survation suggested that were they to be replicated the seat could swing to UKIP, albeit by the narrowest of margins (0.9%). There are, however, good reason to doubt that local election results are a strong predictor of General Election performance as voter turnout tends to be significantly lower.

Steve Stanbury,UKIP’s candidate for Forest of Dean, is calling for a public debate about the use of local taxpayer money to fund foreign aid. He also joined his party’s successful campaign for Rochester and Strood last month.

Verdict: The swing to UKIP in the local elections was significant but even if they come close to a repeat performance at the General Election, it still looks like the Conservative advantage would be difficult to overturn. Unlikely.

8. Sittingbourne and Sheppey

Sittingbourne and Sheppey is a coastal seat in the far north east of Kent that was created in 1997 out of a large part of the old Faversham constituency, which the Conservatives had held continuously since 1970. The Tories then failed to win the newly-created seat until 2010 having lost out by only 79 votes to Labour in 2005.

The 2005 performance was widely attributed to the personal following of its local Labour MP and former England rugby player, Derek Wyatt, who stood down in 2010. With his departure Labour were comfortably swept aside as the Conservative Gordon Henderson took 50% of the vote, a huge 12.7% swing, with UKIP garnering only 5.4%.

In January Richard Palmer was announced as the UKIP candidate for Sittingbourne and Sheppey. The official UKIP constituency website quotes him as saying:

“As an ordinary working family man who has struggled with bringing up a young family whilst working in the NHS as a Paramedic, I feel I can identify with the various needs of people in this constituency.”

Survation’s extrapolation from local election results gives a majority of 5.7% for UKIP, but such a result would require a huge swing from the Conservatives that current national polling does not support.

Verdict: The Conservative margin of victory in 2010 is a daunting challenge for UKIP. The party’s impressive result in local elections suggests they are on track to take a significant proportion of the vote but will it be enough? Possible but unlikely.

9. Aylesbury

Aylesbury has been a Conservative seat since Sir Alan Hughes Burgoyne was elected as its representative in 1924. In fact the Tories have increased their share of the vote in every General Election from 2001 and even held up well in the party’s disastrous 1997 election that saw a resurgent Labour romp home with a huge majority.

In other words, this one is something of a long shot.

However, UKIP did come top in the May 2013 local elections winning 33.4% versus 29.5% for the Conservatives. Support for the Tories is strong in the rural parts of the constituency but the party came fourth in Aylesbury itself, where UKIP polled strongly.

The key local issue is the new High Speed 2 train line route that is bitterly opposed by a number of local residents. An article in The Bucks Herald in March described Aylesbury as “the forgotten victim of HS2″ as it would bring “construction [that] will be hellish for everyone living and working in Aylesbury”.

Stopping HS2 has been the major theme of the UKIP campaign and has paid dividends at the local level. Turnout in May’s local elections, however, was 30% versus 68% in the 2010 General Election. If those voters come out again next May this seat will pose a huge challenge for Chris Adams, UKIP’s candidate, to take for his party.

Verdict:This one looks to be a long a shot for UKIP. Expect them to do much better than in 2010 but still fall some way short of a win. Highly unlikely.

10. Worthing East and Shoreham

The constituency was won comfortably by the Conservatives in 2010, as it has been since its creation in 1997. However, UKIP posted a creditable performance in the last election with 6.2% of the vote, up from 4.7% in 2005.

If the results of local elections were to be repeated, Survation estimate that UKIP would win a 1.72% majority but given the margin of the Conservatives’ previous victories and the likelihood of much higher turnout next may that is unlikely to prove a safe prediction.

Verdict: UKIP have undoubtedly gained ground in Worthing but whether they can overturn almost two decades of comfortable Conservative margins of victory is another matter. Unlikely.

11. Portsmouth South

Portsmouth South looks set to be one of a number of Lib Dem casualties next May as the party’s share of the vote looks set to collapse into the single digits. MP Mike Hancock held the seat from 1997 but he resigned from the Lib Dems in September over allegations that he had sexually assaulted a constituent.

Recent polls put the Conservatives on course to benefit from the scandal with a Lord Ashcroft poll last month giving them 32% with Labour and UKIP neck-and-neck on 21%.

Verdict: With the party some way behind the Tories it will be hard to turn the tide sufficiently over the next five months. This one is also a long shot. Highly unlikely.

12. Grimsby

Grimsby is one of those rarest of things — a Labour seat targeted by UKIP. Unfortunately for Farage, its exceptional nature does not seem to have aided much in terms of the polling figures.

According to a Lord Ashcroft poll from May UKIP are on course to gather some 25% of the vote in Great Grimsby constituency, ahead of the Conservatives on 23% but well behind Labour’s 37%. What will be most concerning for Labour is not the likelihood of losing the seat but the finding by Survation that 70% of UKIP voters in the seat did not vote Conservative in 2010.

That is, what Grimsby could show is that the image of UKIP as the party of disaffected Conservatives is now well past its sell-by date.

Verdict: Grimsby looks set to remain a solid Labour seat, and while UKIP’s gains here have been notable they have mostly come at the cost of the Conservatives to date. It will be an interesting contest though. Highly unlikely.

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