FACTBOX: Indiana and its presidential primary

(Reuters) - Democratic presidential candidate Hillary Clinton won Indiana's primary election on Tuesday, CBS News projected, keeping her presidential bid alive in the contest against rival Barack Obama for the party's nomination to face Republican John McCain in the general election in November.

Although most U.S. television networks said the outcome of the Indiana contest was still too close to call hours after the polls closed, Obama congratulated Clinton on "what appears to be her victory" in the state.

Here are a few facts about Indiana and its presidential primary:

* Manufacturing accounts for 20 percent of all Indiana jobs, the highest proportion of any U.S. state. New ventures in pharmaceuticals, biofuels and medical sciences are joining established industries like steel, engines, and mobile homes.

* Polls begin to open at 6 a.m. EDT and close by 7 p.m. EDT. Independents and Republicans will be able to vote in the Democratic primary.

* Public opinion polls show Obama and rival Hillary Clinton locked in a neck-and-neck battle in the state. Obama is favored in the industrial northwest, an ethnically diverse, heavily Democratic area that bears many similarities to his nearby Chicago home. Obama, who would be the first black president, also is expected to do well in Indianapolis, home to a large black population.

* Clinton is expected to do well in much of the rest of the state, which is predominantly white and culturally conservative.

* Residents of the state are known as "Hoosiers." The origin of the word is unknown.

* The Indianapolis 500, held on Memorial Day weekend, is one of the world's most established automobile races.

(Compiled by Andy Sullivan)

SOURCES: U.S. CENSUS BUREAU, ALMANAC OF AMERICAN POLITICS, INDIANAPOOLIS MOTOR SPEEDWAY, REUTERS NEWS