Interesting thread,here...
As already stated by others, in 1776 the US couldn't have been a democracy yet, not having an elected government.
Nor was it later a democracy in the classical (Greek) definition of the word - but then, no state on earth is!
In a classical democracy all citizens vote on important issues. This was possible in the Greek city states with their limited franchise (remember that most of the population, namely slaves, women and underage men, could not vote!).
Since this form of government was simply unworkable for any sizable state - think about how much trouble the mechanics of a simple presidential election every 4 years are giving the US even today!

... - I personally would accept a broader definition of democracy and accept any of the abovementioned forms of government as 'democracies' which allow their citizens to freely elect the governments which rule them, no matter by which technical means... (though I find the Electoral College system of the US totally outdated and unwieldy.)
By that definition, the US after 1781 was certainly a democracy and the most democratic system of its time.
![Offtopic [offtopic] [offtopic]](/images/smilies/offtopic.gif)
Interestingly, today we would, for the first time, have the technical means, using computers and the internet, to achieve true democracy in the classical sense. It would be possible to directly vote on important issues.
If there is one issue on which all politicians seem to agree, though, it's not allowing any more direct democracy than they have to... seems we're all much too stupid and uninformed to be allowed to participate directly
