The National Journal explains here.
Rand Paul's speech which held up the nomination of a CIA director and Wendy Davis' which forced the end of a special session of the Texas Legislature both qualified. But it was similar to a speech given by Vermont Senator Bernie Sanders in 2010 - which was also not a filibuster.
A filibuster - according to Wikipedia - is:
a type of parliamentary procedure where debate is extended, allowing one or more members to delay or entirely prevent a vote on a given proposal. It is sometimes referred to as talking out a bill, and characterized as a form of obstruction in a legislature or other decision-making body.The consensus seems to be that the speech had little to do with defunding Obamacare, and more to do with raising Cruz's viability as a 2016 presidential candidate and gathering campaign contributions.
This might have been the first big speech of the 2016 presidential race.
Scary thought.
