Prime Minister David Cameron's Conservatives may have won the British election and ushered their coalition partner out the door, but that doesn't mean it's all smooth sailing for his government for the next five years.

Just seven months after Scotland's pro-independence movement failed in a referendum to break up the 308-year-old political union with England, the Scottish National Party has overturned decades of Labour Party dominance by securing a record-breaking share of the vote.

Voters headed for the polls across Britain Thursday, in a contest that is expected to produce an ambiguous result, a period of frantic political horse-trading and a bout of national soul-searching.