When the Census Bureau announced the first population totals from the 2010 Census for the nation (308.7 million) and for states on Dec. 21, the numbers did not include ethnic or race breakdowns. Those will be released later this year. A new report from the Pew Hispanic Center, using other Census Bureau data, concludes that Latinos played a key role in growth of the nation’s population and growth in states that gained congressional seats because of reapportionment, which is based on census numbers.

Using 2009 population estimates from the American Community Survey, Hispanics accounted for 51% of the nation’s population growth since the 2000 Census, which counted 281 million U.S. residents. From 2000 to 2010, the nation’s population grew 9.7%. From 2000 to 2009 (the last year available), the Hispanic population grew 37%.

Looking at population change for each state and the District of Columbia, Hispanics represent a greater share of eligible voter and resident populations in states that will gain congressional seats than in those states that will lose congressional seats, the report concludes. Hispanics represent 15.2% of eligible voters in the eight states that gained congressional seats, compared with 5.4% of eligible voters in the 10 states that lost congressional seats, according to estimates based on the 2009 American Community Survey. (Eligible voters are defined as U.S. citizens who are 18 years or older.) Latinos also represent 23.6% of the resident populations in states that gained seats, compared with 8.4% in states that lost seats.

The report makes the point that because many Latinos are either too young to vote or are not U.S. citizens, their population growth has not translated fully into electoral strength. However, the report states, “the electoral strength of the nation’s largest minority group will continue to grow in the coming decades.”