According to the U.S. Census Bureau, the county has a total area of, of which is land and is water. Lea County is located in the southeast corner of New Mexico and borders Texas to the south and east. The Permian Basin, 250 miles wide and 350 miles long, underlies Lea County and adjacent Eddy County as well as a big piece of West Texas. It produces 500,00 barrels of crude a day, and this number was expected to double in 2019. The shale in this basin lies 3,000 to 15,000 feet below the surface, below a salt bed and a groundwater aquifer.
As of the 2000 census, there were 55,511 people, 19,699 households, and 14,715 families living in the county. The population density was 13 people per square mile. There were 23,405 housing units at an average density of 5 per square mile. The racial makeup of the county was 67.13% White, 4.37% Black or African American, 0.99% Native American, 0.39% Asian, 0.04% Pacific Islander, 23.81% from other races, and 3.27% from two or more races. 39.65% of the population were Hispanic or Latino of any race. There were 19,699 households out of which 39.30% had children under the age of 18 living with them, 57.80% were married couplesliving together, 12.20% had a female householder with no husband present, and 25.30% were non-families. 22.50% of all households were made up of individuals and 9.90% had someone living alone who was 65 years of age or older. The average household size was 2.73 and the average family size was 3.20. In the county, the population was spread out with 30.10% under the age of 18, 10.10% from 18 to 24, 27.30% from 25 to 44, 20.30% from 45 to 64, and 12.20% who were 65 years of age or older. The median age was 33 years. For every 100 females there were 100.30 males. For every 100 females age 18 and over, there were 99.00 males. The median income for a household in the county was $29,799, and the median income for a family was $34,665. Males had a median income of $32,005 versus $20,922 for females. The per capita income for the county was $14,184. About 17.30% of families and 21.10% of the population were below the poverty line, including 28.00% of those under age 18 and 14.90% of those age 65 or over.
2010 census
As of the 2010 census, there were 64,727 people, 22,236 households, and 16,260 families living in the county. The population density was. There were 24,919 housing units at an average density of. The racial makeup of the county was 75.0% white, 4.1% black or African American, 1.2% American Indian, 0.5% Asian, 0.1% Pacific islander, 16.6% from other races, and 2.6% from two or more races. Those of Hispanic or Latino origin made up 51.1% of the population. In terms of ancestry, 9.3% were German, 7.6% were Irish, 7.2% were English, and 6.3% were American. Of the 22,236 households, 41.9% had children under the age of 18 living with them, 52.8% were married couples living together, 13.4% had a female householder with no husband present, 26.9% were non-families, and 22.6% of all households were made up of individuals. The average household size was 2.82 and the average family size was 3.30. The median age was 31.9 years. The median income for a household in the county was $43,910 and the median income for a family was $48,980. Males had a median income of $44,714 versus $25,847 for females. The per capita income for the county was $19,637. About 15.2% of families and 17.7% of the population were below the poverty line, including 23.5% of those under age 18 and 11.1% of those age 65 or over.
Transportation
Airports
The following public-use airports are located in the county:
In the 2004 Presidential election, Lea County was the top New Mexico county, as far as percentage, for Republican George W. Bush. He beat John Kerry 79%-20%. In 2008, the Republican candidate John McCain beat Democratic candidate Barack Obama by a wide but slightly smaller margin, 72% to 27%.
