Tightest UK election in a generation goes down to the wire

By Andrew Osborn LONDON (Reuters) - A late burst of opinion polls suggested on Wednesday that Conservative Prime Minister David Cameron and Labour challenger Ed Miliband had fought each other to a standstill on the eve of Britain's most unpredictable election in a generation. The stakes are high because of a rare confluence of factors which mean Britain's future in the European Union, as well as its national cohesion, could hinge on the result. "We can achieve an overall majority