The amount of electricity generated in the United States continues to grow. In 2012, wind power supplied about 3.5% of total electrical generation. Last year, wind power grew to 4.1% of the nation's total electrical power. That was 167 million megawatt hours (MWh) of electricity, and a whopping 80.2% of that electricity from wind power (134 million MWh) came from just 12 states. The state producing the most wind power was Texas (with about 36 million MWh), followed by Iowa (with about 15 million MWh).
Those figures are from the U.S. Energy Information Administration's Electric Power Monthly report. The two charts below show the energy output for wind power from the 12 states producing the most wind energy for one month (February of 2014, the last month for which totals are available). The top chart gives each states output in thousands of MWh, and the bottom chart shows how much each state provided as a total of the February national output of wind energy (which was 14,001,000 MWh).
This is a good start, but that's all it is. There is still plenty of room for growth in the wind power industry.