Located in the southwestern portion of the state bordering the lower Delaware River and reaching to the Delaware Bay, the Third District is the state’s largest district in area, covering 788.55 square miles, and ranks lowest of all 40 districts in population density, with 265 people per square mile. It is comprised of all of Salem and parts of Gloucester and Cumberland Counties. The district has a slightly above average proportion of African-Americans, but relatively few Hispanics or Asians. It also contains the lowest number of foreign-born citizens and fourth fewest proprtion of college graduates.

The district remains one of the more undeveloped and rural regions in the state where economic issues, particularly job creation and security, continue to be important for its relative high proportions of middle-class residents and those employed in farming or related industries.

The area now incorporated within the district has one of the more interesting histories in New Jersey. It was first settled along the lower Delaware by Swedes, who were subsequently displaced by the Dutch, who were in turn forced to cede their claims by the British. Later, Quakers acquired much of the land along the Delaware in hopes of founding a cohesive Quaker community, establishing the first meaningful permanent English settlement in the Delaware Valley at Salem in 1675. The goal of the Quakers, was frustrated, however, by the already diverse national and religious affiliations of the existing settlers in the area, and they soon decided to shift their efforts west to the more unsettled frontier of present-day Pennsylvania.

Coastal towns along the Delaware and Maurice Rivers formerly were key fishing and shipping ports, but the once thriving shellfish industry was severely impacted by the blight that nearly wiped out the industry. The sandy soils through much of the region also aided in the establishment of glass manufacturing; the Salem Glass Works in Salem was founded in 1863 to manufacture bottles and fruit jars, and is now the container division of the Anchor Glass Corporation, one of the largest producers of glass containers in the United States.

In 1933, Charles F. Seabrook founded Seabrook Farms Corporation near Bridgeton, which became one of the largest producers and processors of frozen vegetables in the world, and during World War II also served as the worksite for Japanese-American internees who were arrested after the bombing of Pearl Harbor, with many remaining to work voluntarily at Seabrook even after they were released at the end of the War from the terms of their confinement.Today, a successor company founded in 1978 by Seabrook’s three grandsons operates as Seabrook Brothers & Sons, freezing snap beans, spinach, collards, mustard greens, peppers, peas and lima beans in a modern plant located in Upper Deerfield Township surrounded by farmland. See Review of Seabrook at War: A Radio Documentary, The Journal for Multimedia History. Other major employers include Mannington Mills in Salem, founded in 1915 by Scottish immigrant John Campbell and his sons, and now one of the nation's leading manufacturers of floor coverings and the Salem and Hope Creek nuclear generating plants in Lower Alloways Township.

Democratic Senator Stephen Sweeney, a labor union official, was first elected in 2001, defeating incumbent Republican (and former Democrat) Raymond Zane by 1,735 votes in a campaign featuring the highest spending of all 40 districts. At the commencement of the January 2010 legislative session, Senator Sweeney was elected by the Senate Democrats as Senate President, the highest Senate leadership position, defeating veteran Senate President Richard Codey of Essex County,

The Assembly seats are also held by two Democrats: John Burzichelli and Celeste Riley. Assemblyman Burzichelli, now serving his fourth term, is managing partner of Hill Studio in Paulsboro, a sound stage facility that provides studio services and special effects to the motion picture, video and still photography industry. Assemblywoman Riley, a teacher at the Morris Goodwin Elementary School in Greenwich and a former Bridgeton City Council President, was sworn in March 16, 2009 to fill the vacancy created when Assemblyman Doug Fisher resigned his seat to accept appointment as Secretary of the New Jersey Department of Agriculture. She is the first woman to represent the 3rd Legislative District and the first woman representative from Cumberland County.

In the 2009 election, both Assembly incumbents were easily re-elected over their Republican opponents--Lee Lucas of Gibbstown and Robert Villare of West Deptford. The Republican campaign was undermined by internal splits within the Republican organization and personal issues affecting both of the Republican nominees.