This is an extraordinarily complicated question, one that I doubt that anyone could answer satisfactorily here. I'll give it a bit of a whirl.

The short answer: No. The medium answer: well maybe a little. Here's what I mean. The French Revolution was defined by the overturning of an entire political ordering that had existed, with little variation, for over a thousand years. The pillars of the French state, absolute monarchy, Catholicism, and nobility were overturned in a manner of years to institute a radical political state. Not only did the people in charge change, but how political power instantiates itself changed. Louis XIV famously stated "L'etat c'est moi" (I am the state). The Abbe Sieyes, on the eve of revolution, in his pamphlet "What is the Third Estate?" wrote that the peasantry makes up the entirety of the nation. Those that work deserve not just a share in political power, but are the body of the state as a whole. When Louis XVI was executed, he was executed as an enemy of the state, a foreigner because he attempted to subvert the states' power.

So let's look at the American Revolution. Of course the people in power changed, and the country was no longer ruled from Britain. But in essence, the dialectic of power remained remarkably similar. The same elites that ruled the colonies in the colonies remained the same - there simply was now no longer any level of government above them. American Revolutionaries believed they were attempting to claim rights that were guaranteed of them as British citizens. Sweeping aside the entire structure of how state power was formed was not their main goal, nor was it what was accomplished.

In this way, the prototypical revolution has always been the French Revolution rather than the American Revolution. This is because the drastic changes of the French Revolution lends itself to groups wanting a total overturn of political society. This was unprecedented. Rulers had come and gone throughout all of history - but the structures that they used to rule all resembled each other. That is until the French Revolution. In this way it is impossible that the American Revolution influenced the French Revolution, simply because they were two totally different things. In fact, the American Revolution was always called the American War for Independence, until the French Revolution occurred. So even on a purely semantic level, the answer is most likely, no, not really.

French soldiers certainly took part of the American revolution, and when they returned, they spread ideas of liberty and freedom into a society that was divided rigidly into social strata. One of the main figures here was the Marquis Lafayette, who as an ardent supporter of the United States' constitutional principles, called on all nations to follow the American example.

He went on to play a critical role in the revolution, and the Declaration of the Rights of Man and of the Citizen was largely based on his draft, with the assistance of Thomas Jefferson. Lafayette became head of the National Guard, and played a prominent role in affairs, so certainly his ideas would have influenced the course of the revolution. Whether he maintained his American revolutionary ideals is subject to debate. The Champs de Mars massacre, where Lafayette was in charge of troops which fired into a crowd of republicans protesting against a constitutional monarchy (believing it did not go far enough), suggest that he did not maintain his American philosophy.

However, the role of America in influencing the revolution was by no means the sole factor. The works of Montesquieu, Rousseau and Voltaire, as the most notable voices of French intellectual culture, but not the only voices, had a significant role in influencing many of the nobles who would support the Third Estates demand for more representation.

I don't have time for a more in-depth answer right now, but there were other figures involved, and I'll be happy to answer any questions.

Would the French Revolution happen if the American Revolution had lost? What if it didn't happen at all?