NEWARK England/LONDON (Reuters) - Prime Minister David Cameron's Conservatives are poised to win a vote for a parliamentary seat on Thursday despite being beaten into third place by an insurgent Eurosceptic party in last month's European elections.
Cameron and his party are likely to seize on the victory in Newark, in the English county of Nottinghamshire, as proof that the outcome of the European elections was a one-off protest that will not be replicated at a national election in May next year.
The UK Independence Party (UKIP), which wants stricter border controls and for Britain to leave the European Union, won the European elections, the first time that such an election has not been won by either the Conservatives or the opposition Labour party in more than a century.
Tapping into a general feeling of discontent with politicians and their perceived inability to effect change, UKIP siphoned support from all three of Britain's mainstream parties.
However, polling showed it drew most of its support from former Conservative voters, raising the prospect it could split the centre-right vote next year, making it harder for Cameron to be re-elected.
Two opinion polls conducted before Thursday's vote forecast the Conservatives would win with a lead of between eight and 15 percentage points. The polls showed UKIP would come second, Labour third and the Liberal Democrats fourth.
UKIP is likely to portray a strong showing in Newark, traditionally a safe Conservative seat and not one that UKIP would usually target, as another sign that it is a force in British politics with which to be reckoned.
Lacking an established party machine or historical support base in the largely rural constituency, Patrick O'Flynn, UKIP's spokesman, said before the vote that the party would try to win. But he likened the challenge to "going from base camp to the summit of Mount Everest in about half an hour".
UKIP came fourth when the seat was last contested at a national election in 2010 winning just 3.8 percent of the vote or less than 2,000 individual votes.
By contrast, Cameron's party won by a margin of more than 16,000 votes in 2010 taking 53.9 percent of the vote. Labour came a distant second, and the Liberal Democrats third.
Rattled by its third place finish in last month's European elections the Conservatives were not taking any chances with Newark however. Cameron visited four times and the party ordered activists, lawmakers and ministers to campaign there too.
Thursday's election was triggered by the resignation of the sitting Conservative member of parliament Patrick Mercer after he was compromised in a lobbying scandal.
Results are due from 2 a.m. on Friday.
(Writing by Andrew Osborn; Editing by Guy Faulconbridge)