Houston ? The United States grew steadily more diverse last year, with Hispanics holding on to their rank as the nation’s largest and fastest-growing minority group – a trend with far-reaching implications for American politics and immigration policies.

Newly released figures from the U.S. Census Bureau show that the nation’s Hispanic population grew by 1.4 million in 2007 to reach 45.5 million people, or 15.1 percent of the total U.S. population of 301.6 million. African-Americans ranked as the second-largest minority group, at 40.7 million people.

Overall, the nation’s 102.5 million minorities accounted for 34 percent of the U.S. population, a new milepost on America’s inexorable journey toward greater diversity and a harbinger of the growing political clout of non-whites.