Story highlights Here's a look at why Kaine's addition to the ticket is notable in U.S. history

17 of the last 18 Democratic conventions have nominated for vice president someone who had served in the Senate

(CNN) Hillary Clinton is hoping her decision to tap Virginia Sen. Tim Kaine as her running mate will go down in history as a move that helped her capture the presidency, but it's already rife with historical implications. Here's a look at why Kaine's addition to the ticket is notable in US history.

Sitting senator

Kaine's selection extends a remarkable streak in which 17 of the last 18 Democratic conventions -- including the last eight in a row -- have nominated for vice president either a sitting senator or an incumbent vice president who was a senator when he was first elected.

The lone exception between 1944 and 2012 is 1984, when New York Rep. Geraldine Ferraro was nominated to join Walter Mondale on the ticket. Also note that in 1972, the Democratic convention nominated Sen. Thomas Eagleton, who subsequently left the ticket and was replaced by Sargent Shriver, who had never served in the Senate.

The complete list: 1944: Sen. Harry Truman; 1948: Sen. Alben Barkley; 1952: Sen. John Sparkman; 1956: Sen. Estes Kefauver; 1960: Sen. Lyndon Johnson; 1964: Sen. Hubert Humphrey; 1968: Sen. Ed Muskie; 1972: Eagleton (replaced by Shriver); 1976: Mondale (then a Minnesota senator); 1980: Mondale; 1988: Sen. Lloyd Bentsen; 1992: Sen. Al Gore; 1996: Gore; 2000: Sen. Joe Lieberman; 2004: Sen. John Edwards; 2008: Sen. Joe Biden; 2012: Biden.

Photos: Tim Kaine selected as Hillary Clinton's running mate Presumptive Democratic presidential nominee Hillary Clinton arrives with Sen. Tim Kaine at a rally in Miami on Saturday, July 23. Clinton has selected Kaine as her running mate. Kaine has represented Virginia in the Senate since January 2013. He was governor from 2006 to 2010. Hide Caption 1 of 20 Photos: Tim Kaine selected as Hillary Clinton's running mate Kaine greets people at a Herndon, Virginia, homecoming parade on October 6, 2001. He was mayor of Richmond at the time and running for lieutenant governor. Hide Caption 2 of 20 Photos: Tim Kaine selected as Hillary Clinton's running mate While running for governor, Kaine was supported by then-U.S. Sen. Barack Obama. Here, the two attend a fundraiser in Arlington, Virginia, in 2005. Hide Caption 3 of 20 Photos: Tim Kaine selected as Hillary Clinton's running mate Kaine attends a campaign rally in Richmond in 2005. Hide Caption 4 of 20 Photos: Tim Kaine selected as Hillary Clinton's running mate Gov. Kaine and his wife, Anne Holton, acknowledge the crowd after his inauguration in 2006. Hide Caption 5 of 20 Photos: Tim Kaine selected as Hillary Clinton's running mate Kaine talks on Capitol Hill with Senate Minority Leader Harry Reid and House Minority Leader Nancy Pelosi in 2006. Hide Caption 6 of 20 Photos: Tim Kaine selected as Hillary Clinton's running mate Cadets from the Virginia Military Institute and Virginia Tech salute as Kaine and Britain's Queen Elizabeth II enter the Virginia State Capitol in 2007. Hide Caption 7 of 20 Photos: Tim Kaine selected as Hillary Clinton's running mate Obama and Kaine applaud as U.S. Sen. Jim Webb speaks at a rally in Bristow, Virginia, in 2008. Hide Caption 8 of 20 Photos: Tim Kaine selected as Hillary Clinton's running mate Kaine and U.S. President George W. Bush attend a naturalization ceremony in Charlottesville, Virginia, on July 4, 2008. Hide Caption 9 of 20 Photos: Tim Kaine selected as Hillary Clinton's running mate In 2008, Kaine gives a guided tour of the grounds at Fort Monroe in Hampton, Virginia. Hide Caption 10 of 20 Photos: Tim Kaine selected as Hillary Clinton's running mate Kaine, as chairman of the Democratic National Committee, speaks at the University of Pennsylvania in 2010. Kaine served as the committee's chairman from January 2009 to April 2011. Hide Caption 11 of 20 Photos: Tim Kaine selected as Hillary Clinton's running mate Kaine takes the stage with his wife and daughter Annella after winning his Senate race in 2012. Kaine has three children. Hide Caption 12 of 20 Photos: Tim Kaine selected as Hillary Clinton's running mate U.S. Vice President Joe Biden, right, administers the Oath of Office to Kaine during a mock swearing-in ceremony in 2013. Hide Caption 13 of 20 Photos: Tim Kaine selected as Hillary Clinton's running mate Kaine attends a hearing of the Senate Foreign Relations Committee in 2015. Hide Caption 14 of 20 Photos: Tim Kaine selected as Hillary Clinton's running mate Kaine shows the photo of a 3-year-old drowned Syrian boy during a Capitol Hill news conference in 2015. Politicians and religious leaders had come together to discuss the Syrian refugee crisis. Hide Caption 15 of 20 Photos: Tim Kaine selected as Hillary Clinton's running mate Kaine gives a thumbs-up at the National Prayer Breakfast in February. Hide Caption 16 of 20 Photos: Tim Kaine selected as Hillary Clinton's running mate Kaine meets in April with Judge Merrick Garland, Obama's choice to replace the late Justice Antonin Scalia on the U.S. Supreme Court. Hide Caption 17 of 20 Photos: Tim Kaine selected as Hillary Clinton's running mate U.S. Sen. Tim Kaine, a Democrat from Virginia, questions witnesses during a Foreign Relations Committee hearing on May 26. Hide Caption 18 of 20 Photos: Tim Kaine selected as Hillary Clinton's running mate Kaine, along with World War II veterans and Senate Minority Leader Harry Reid, attend a news conference on Capitol Hill on June 9. Hide Caption 19 of 20 Photos: Tim Kaine selected as Hillary Clinton's running mate Kaine waves with Hillary Clinton during a campaign event in Annandale, Virginia, on July 14. Hide Caption 20 of 20

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