|The Liberal Democrats face a system that favours the Labour and Conservative parties [EPA]
Few would deny that the Liberal Democrats, Britain's third largest political party, have so far enjoyed an unexpectedly good election campaign.
Two assured performances by Nick Clegg, the party leader, in the televised debates have given them a surge in support, with most polls placing them ahead of the ruling Labour party and some even showing them overtaking the frontrunning Conservative party.
Yet even if they build on this momentum, Britain's electoral system makes it highly unlikely that they will win enough seats in parliament to form a majority government.
In fact, the system could throw up a counter-intuitive scenario in which they win a larger share of the popular vote than their rivals, but end up with fewer seats in parliament.
So what is going on? The main reason for this electoral quirk is Britain's first-past-the-post method of electing legislators. Under the rules, the country is divided into 650 constituencies, one for each seat of parliament.
Winner takes all
Voters cast their ballot to decide who represents their constituency - it is down to the political party with the majority of parliamentary seats after the election to decide which of their MPs become ministers (which is how Gordon Brown, the current prime minister, took office without an election).
In each constituency, the candidate with the most votes is declared the winner. There is no prize for second place.
On the surface, it seems a straightforward system that ensures the most popular candidates from each constituency are elected to parliament.
But because several candidates run in each constituency, the vote is split many ways and most return MPs who the majority of residents did not vote for - those MPs that won their constituency with less than 50 per cent of the vote.
Because the votes for losing candidates are disregarded, a party can come away from a national election with a smaller parliamentary representation than its share of the popular vote would suggest.
Turning support into constituency wins is the name of the game in first-past-the-post politics. It is also the Liberal Democrat's greatest weakness.
The two largest parties enjoy support that is concentrated in geographical areas, while Liberal Democrat support is comparatively consistent across the country.
Polls might put Labour support lower than the Liberal Democrats nationally, but in the north of the country Labour is by far the most popular party, meaning it is easier for them to win constituencies there.
Likewise, Conservative support is concentrated in the south; their national average is dragged down by their unpopularity in the north, but they remain favourite to return MPs from many southern constituencies.
The Liberal Democrats do not have the same geographical strongholds making it harder for them to come first in as many constituency races.
That means they can do well in national opinion polls but win relatively few seats in parliament.
Some analysts predict that the Liberal Democrats will come second in almost half the constituencies in the country, but none of these votes will count towards the make-up of the new parliament.
Unsurprisingly, electoral reform is a key Liberal Democrat policy. They want to see a proportational system where national support is translated into parliamentary representation.
But neither Labour nor the Conservatives want to abandon the first-past-the-post system, arguing that proportional representation would make future governments less stable because they will likely be formed of more than one party.
But that debate is for the future. At present, there are no silver medals in the British electoral system.
Second place is first loser, regardless of how popular that loser is, and no matter how well the Liberal Democrats do in opinion polls between now and the election, the prospect of the country waking up to a Prime Minister Clegg on May 7 remains extremely unlikely.