FACTBOX: North Carolina's presidential primary

(Reuters) - Democratic presidential candidates Hillary Clinton and Barack Obama have campaigned heavily in North Carolina before its primary election on Tuesday.

Following are some facts about North Carolina:

* With a population of 9.1 million, North Carolina is one of the country's fastest-growing states. Industries like banking, pharmaceuticals and high technology have transformed an economy formerly dominated by textiles, furniture and tobacco.

* Obama is expected to win, thanks to his strong support among blacks, who make up 22 percent of the state's population, well above the national average.

* Opinion polls show Obama leading by an average of 10 percentage points, although the state's governor, Mike Easley, recently endorsed Clinton.

* Voting concludes at 7:30 p.m. (2330 GMT).

* Former North Carolina Sen. John Edwards was the 2004 Democratic vice presidential nominee, but Republican President George W. Bush won the state with 56 percent of the vote. Edwards launched a bid for president in 2007 but dropped out in January and has yet to endorse either Obama or Clinton.

(Compiled by Andy Sullivan; Editing by Peter Cooney)

Sources: U.S. Census Bureau, Almanac of American Politics, Real Clear Politics, Reuters News, North Carolina Barbecue Society

(To read more about the U.S. political campaign, visit Reuters "Tales from the Trail: 2008" online at blogs.reuters.com/trail08/)