FACTBOX: New Jersey and its presidential primary

(Reuters) - New Jersey is among 24 states taking part in "Super Tuesday," the February 5 contests in which voters will choose nominees from the Democratic and Republican parties for the November U.S. presidential election.

Following are a few facts about New Jersey and its primary:

* Television advertising in New Jersey can be expensive, as the state is dominated by the large media markets of New York and Philadelphia. New York, home to Democratic candidate Sen. Hillary Clinton, holds its primary on the same day.

* A Reuters/C-SPAN/Zogby poll taken over the weekend showed Clinton in a dead heat with rival Illinois Sen. Barack Obama, with 43 percent each and 10 percent undecided. Among Republicans, Arizona Sen. John McCain led former Massachusetts Gov. Mitt Romney 52 percent to 26 percent.

* Polls close at 8 p.m./0100 GMT Wednesday. Democrats allocate delegates on a proportional basis, while all of the Republican delegates go to the winner of that contest.

* With a population of 8.7 million, New Jersey is the most densely populated state. The state's median household income of $66,752 was highest in the nation in 2006.

* New Jersey is home to many pharmaceutical companies, which have come under fire in the health care debate for high prices and heavy marketing practices.

* For much of the 20th century, New Jersey was a competitive state in national elections, but has leaned Democratic since the 1990s. Among registered voters, 24 percent are Democrats and 18 percent are Republicans.

* The state's working-class culture has been celebrated by rocker Bruce Springsteen and "The Sopranos" TV show. In recent years, the state has drawn large numbers of immigrants.

Sources: Almanac of American Politics, U.S. Census Bureau

(Reporting by Andy Sullivan; Editing by Stacey Joyce)