Sandra Bolden was born on September 4, 1950, and was raised in Newark. She graduated from West Side High School and received a B.A. from Bloomfield College with a major in liberal arts.
Following her husband's death, there were reports of interest by Cunningham to seek her late husband's Senate seat to which he was elected in 2003 and was reported to be considering a run for Mayor of Jersey City in a May 2005 special election. She became president of the Sandra and Glenn Cunningham Foundation and has supported causes in Jersey City through the foundation. In 2006 signs in Jersey City touted her as a candidate for the U.S. Senate vs. Sen. Robert Menendez and State Sen. Tom Kean Jr.. Menendez and her late husband were bitter political rivals. She did not seek the U.S. Senate seat and announced her candidacy for the state senate in the Democratic primary against Sen. Joseph Doria in 2007. Doria, the mayor of Bayonne, dropped out of the race in March 2007. Assemblyman Louis Manzo, who first won his seat on a ticket with Mayor Cunningham, challenged Cunningham in the Democratic primary for the Senate. During the primary race, Cunningham received the support of the Hudson County Democratic Organization and Jersey City Mayor Jerramiah Healy, who had previously opposed her and her late husband. One of Cunningham's running mates for the Assembly was former State Sen. L. Harvey Smith, who had been defeated by her husband in a bitter 2003 Senate primary. Cunningham defeated Assemblyman Manzo in the Democratic primary in June 2007. She was virtually unopposed in the November general election, defeating independent candidate Louis Vernotico with over 87% of the vote. Following Doria's October 2007 resignation to become Commissioner of the New Jersey Department of Community Affairs, Cunningham was elected on October 23, 2007, by a special election convention to serve the remainder of Doria's term, which expired in January 2008. Cunningham served the remainder of Doria's term before beginning her own four-year term and was sworn into the state senate on November 8, 2007. In the Senate, she has been assigned to serve as chair of the Higher Education; she also sits on the Budget and Appropriations Committee and Labor Committee. She is the current senate majority whip, holding the position since 2008. In 2012, the Hudson Reporter named her #6 in its list of Hudson County's 50 most influential people, with North Bergen mayor and State Senator Nicholas Sacco ranked first on the list.
She began dating Jersey City police officer and councilman Glenn Cunningham in 1990 and got married on January 7, 1998, in Nassau, Bahamas. While Cunningham was campaigning for and later won the Jersey City mayoral election in 2001, Sandra Cunningham often accompanied her husband at public events and political meetings. Glenn Cunningham died on May 25, 2004, of a heart attack.