British Prime Minister Gordon Brown's Labour party gained an opinion poll boost on the final day of campaigning ahead of Thursday's election, but three national newspapers came out in support of opposition parties.
Conservative leader David Cameron campaigned through the night and Brown made an early visit on Wednesday morning to market workers in northern England to woo the one-third of voters said still to be wavering.
A YouGov poll for the Sun newspaper suggested the centre-right Conservatives' momentum had stalled, putting them unchanged on 35 percent, while centre-left Labour rose to 30 per cent.
The Liberal Democrats, who had been enjoying a strong rise in support on the back of a higher profile for their telegenic leader Nick Clegg, fell four points to 24 perc ent.
The quirks of the British electoral system, in which voters elect a member of parliament from their local constituency, mean that these figures would allow Labour to remain the biggest party, but short of a majority in parliament.
Labour has been in power since 1997, but has been battered by recession and public anger over a parliamentary expenses scandal that has tainted all the main parties.
A ComRes poll for the Independent newspaper put support for the parties unchanged, with the Conservatives 8 points ahead of Labour, making David Cameron's opposition party the largest in a 650-seat parliament, but denying him outright control.
Both polls suggest a 'hung parliament', in which the centrist Lib Dems could hold the balance of power.
Britain has not had an inconclusive election of this kind since 1974 and is not used to the kind of coalition-building familiar to many countries in continental Europe.
Two senior Lib Dem party members said on Wednesday they would work constructively with whoever the British public decided should lead the country, but reiterated their view that they could not support a party that won the most seats despite coming third in votes.
"We would be willing to talk to other parties, depending on how people vote," Lib Dem finance spokesman Vince Cable told BBC radio.
Northern Ireland's Democratic Unionist Party, which is expected to win at least nine seats, is willing to enter into a formal coalition with the Conservatives if they fail to win an overall majority, the Daily Telegraph newspaper reported.
The paper said the DUP would require Cameron to protect the region from this year's public spending cuts. Conservative schools spokesman Michael Gove denied any deal had been done, saying the party was campaigning for an outright win.
Two mass-circulation newspapers said a hung parliament would make it harder to solve Britain's economic woes, backing the Conservatives for their commitment to cut a public deficit running at more than 11 percent of GDP faster than Labour would.
The Daily Express said Cameron had earned the right to govern, and said his Conservative party needed a clear mandate to "get Britain going in the right direction again".
The Daily Mail backed Cameron's commitment to a smaller state and cutting public spending rapidly, saying Britain needed a decisive government to avoid a Greek-style crisis.
The Independent newspaper came out in favour of the Lib Dems, supporting their stance on electoral reform. It said that, in Conservative/Labour swing seats, people should consider voting Labour to keep the Conservatives out.