The district has been progressing in a different direction in the past few years, turning from a once reliable Republican district to a competitive district as it has become more ethnically mixed with Caucasians comprising, as of 2009, 79% of the district, African Americans 5.7%, Asians 11% and Latinos 10%. In addition, the district is home to a large group of foreign-born residents, totaling 131,000 or 20% of the population. In spring 2017, several Democrats have indicated they will challenge incumbent Leonard Lance in the 2018 election, and they include Scotch Plains lawyer Scott Salmon, Westfield teacher and attorney Lisa Mandelblatt, Berkeley Heights banking executive Linda Weber and former Assistant Secretary of State for Democracy, Human Rights, and Labor and human rights advocate Tom Malinowski.
In the 2012 general election, Republican incumbent Leonard Lance held his seat against Democratic challenger Upendra J. Chivukula. In the 2010 general election, Democratic challenger Ed Potosnak challenged Lance, but Lance defeated Potosnak by a margin of 59% to 41%. For the 2012 election, both Potosnak and former Edison Mayor Jun Choi announced their candidacies for the Democratic nomination. Choi dropped out of the race in December 2011 after redistricting left his Edison home outside the 7th District. Potosnak dropped out of the race in January 2012 to take a position as executive director of the New Jersey League of Conservation Voters, leaving a momentarily empty field for the Democratic nomination.
In 2008, Mike Ferguson (who had first been elected in 2000, replacing Bob Franks) did not seek another term. Linda Stender won the Democratic nomination unopposed, while Republican primary voters chose State Senator Leonard Lance in a field of eight candidates. In the general election, Lance defeated Assemblywoman Linda Stender by a margin of 25,833 votes.
Linda Stender campaigned on the issues of stem cell research and the Iraq War, while Mike Ferguson campaigned on the issues of Ms. Stender's prior legislative record and her close ties to New Jersey's Democratic political machine.
New Jersey's 7th district and the 12th district were redistricted after the 2000 census by a bipartisan panel. By consensus of the panel, the Democratic and Republican parties agreed to trade areas in the two districts to make them safer for their respective incumbents. It is likely that this tradeoff, which made New Jersey's 7th less competitive for Democrats, had an effect on the outcome of 2006 election, which was decided by approximately 3,000 votes. Areas of the former 7th district such as Somerset in Franklin Township (Somerset County) that had historically voted reliably Democratic were moved into the adjacent 12th district to shore up the Democratic incumbent's hold on there, while reliably Republican Millburn was moved into the 7th. Despite the redistricting, NJ-07 is still the most competitive House district in New Jersey, and was the only one considered to be in play in 2006 by political pundits.
^Jonathan D. Salant (May 3, 2017). "They're already lining up to challenge N.J.'s Lance in 2018". NJ.com (Advance Media). Retrieved May 8, 2017. ...Lisa Mandelblatt, a teacher in Westfield, and Scott Salmon, a lawyer from Scotch Plains, are vying for the Democratic nomination for an election still 18 months away....Salmon, 27, called Trump's election "the breaking point" and decided that he needed to run against a lawmaker who endorsed the GOP nominee....