Americans and others who live in two party democracies must be puzzled by the political scene in Britain. Ever since the Liberal Democrats started to gain significant numbers of parliamentary seats (46 in 1997, 52 in 2001 and 62 in 2005) we have had a three party system across the whole of Great Britain.  If we take the last election as an example the Labour Party gained 9.6 million votes, the Conservatives 8.7 million and the LibDems nearly 6 million. Our first past the post electoral system has always penalised minor parties – but with the votes of 22% of those who voted the LibDems surely deserved more than the less than 10% of the seats they actually won.

I mention these figures to illustrate that as of the last election parties of the Left (Labour and the LibDems) won 57% of the votes cast and the party of the right, the Conservatives, won just over 32%. In American terms the Democrats wiped the floor with the Republicans by a plurality of well over 20%.

Roll forward to today and let’s take a look at the latest opinion poll at the nadir (one assumes) of Labour’s fortunes. This “poll of polls”, which pulls together the results of various recent opinion polls, said that in July the Conservatives averaged 44%, Labour 27% and the Liberal Democrats 18%.If those results were replicated at a general election, the Tories would win 391 seats and David Cameron would enter Downing Street with a majority of 132.

But look again. The two parties of the left add up to 45% to the Conservatives 44% – and this, remember, is with a Labour party at it’s weakest ever point in modern times and with a resurgent Conservative Party winning elections in local government across the country.

Now there are some dangers with this type of analysis – not least the fact that for many Labour supporters the Labour Party of Blair and Brown has not been a party of the Left at all. It is certainly true that to win in 1997 and to be re-elected twice later Blair eschewed the hard left politics that had denied Labour power for so long. He was a policy pragmatist – a positioning that Brown went along with. But Labour are not pink Tories, albeit that they may not strictly speaking be socialists either. The LibDems are to their Left in the political spectrum, but not by much. And that spectrum is cloudier then ever with some of David Cameron’s tentative policy positions sounding not just “Wet” (a favourite Thatcherite term of abuse) but positively soaking.

But however “One-Nation” some of Cameron and his Shadow cabinet’s positions may seem to be the suspicion remains that given a chance (and a whopping majority at a 2010 Election would be that chance) all the old Conservatives priorities would return. The public face might be genial and all-encompassing, but there are plenty of Thatcherites and neo-Thatcherites around – especially among those waiting to be elected from the marginal constituencies that the Tories are targeting so skillfully.

So if the Left, even today, has a narrow majority in the polls and if we can assume that some recovery by Labour and the LibDems holding their position as well by 2010 the Left should have a clear lead again. But they can still lose the election by a big majority because of the electoral system.

I am not, necessarily, arguing either for electoral reform or for a merger of Labour and the LibDems (although either would make the electoral system fairer and the choices less opaque). What I am pointing out that for all their celebrations of their current position in the polls the Tories have not convinced the majority of the British electorate that they should be the choice. It’s close, but they are not in the lead, despite what they may think! In American parlance the Democrats still have the edge – despite all of Mr Brown’s troubles. Food for thought!