it's not a race but a category in which to classify many like mexicans,cubans, puerto ricans...etc
since i am mexican-american i consider myself Latina. but mainly the category is used or comes in handy in the u.s. where they are trying to get those voters support in the u.s.. i don't know that's the logic i see behind it.
here's my source to back up what i am saying :
Hispanic or Latino Americans are Americans with origins in the Hispanic countries of Latin America or in Spain, and in general all persons in the United States who self-identify as Hispanic or Latino.[2][3][4][5][6]
Reflecting especially the Latin American population, which has origins in all the continents and many ancestries,[7] Hispanic/Latino Americans are very racially diverse, and as a result form an ethnic category, rather than a race.[5][8][9][10] The choice of name is associated with location: Hispanic and Latino Americans who reside in the eastern United States tend to prefer the term Hispanic, whereas those in the west usually prefer Latino.[4]
Hispanics or Latinos constitute 16.3% of the total United States population, or 50.5 million people,[1] forming the second largest ethnic group, after non-Hispanic White Americans (a group composed of dozens of sub-groups, as is Hispanic and Latino Americans).[11] Hispanic and Latino Americans are the largest of all the minority groups, but Black Americans are the largest minority among the races, after White Americans in general (non-Hispanic and Hispanic).[12] Mexican Americans, Cuban Americans, Colombian Americans, Dominican Americans, Puerto Ricans, Spanish Americans, and Salvadoran Americans are some of the Hispanic and Latino American national origin groups.[13]
There have been people of Hispanic or Latino heritage in the territory of the present-day United States continuously[14][15][16][17] since the 1565 founding of St. Augustine, Florida, by the Spanish, the longest among European American ethnic groups and second-longest of all U.S. ethnic groups, after Native Americans. Hispanics have also lived continuously in the Southwest since near the end of the 16th century, with settlements in New Mexico that began in 1598, and which were transferred to the area of El Paso, Texas, in 1680.[18] Spanish settlement of New Mexico resumed in 1692, and new ones were established in Arizona and California in the 18th century.[19][20] The Hispanic presence can even be said to date from half a century earlier than St. Augustine, if San Juan, Puerto Rico is considered to be the oldest Spanish settlement, and the oldest city, in the U.S.[21]
For the U.S. government and others, Hispanic or Latino identity is voluntary, as in the United States Census and in some market research.[22]