(Reuters) - The race to win the Republican Party's presidential nomination to challenge President Barack Obama turns to 10 states holding primaries and caucuses on "Super Tuesday," including Tennessee.
Here are a few facts about the Tennessee Republican primary.
* Tennessee's primary is expected to be a tussle between former Massachusetts Governor Mitt Romney, Rick Santorum, a former U.S. senator from Pennsylvania, and former U.S. House Speaker Newt Gingrich. Santorum had been leading Romney in opinion polls but that gap has narrowed to a virtual statistical tie. Following close behind is Gingrich, from neighboring Georgia, who hopes for a strong showing to help revive his campaign.
* In the 2008 Tennessee primary, Romney came in third, winning about 24 percent of the vote. A Romney win in the southern conservative state would be considered an upset.
* Tennessee had an estimated population of 6.4 million people in 2011, with a faster growth than the national average. Two thirds of the residents of the state are Caucasian followed by African Americans, who make up nearly 17 percent, while 4.6 percent are Hispanic.
* Tennessee was hit hard by the economic downturn. The state's unemployment rate was 8.5 percent in December 2011, similar to the national average, reflecting job cuts trade, transportation, and hospitals, according to the state government.
* Median household income in Tennessee has dropped to $43,314 making it one of the country's poorest states. In 2010, 16.5 percent of Tennessee residents were beneath the poverty line compared with the national rate of 13.8 percent.
(Reporting By Lily Kuo; Editing by Deborah Charles and Doina Chiacu)