The Senate might not have any African-American members after the election, when Sen. Roland Burris (D-Ill.), the only sitting black senator, vacates his seat.

Overall, the Senate has never had more than one black member at a time. Burris replaced President Obama in this distinction after filling his Illinois seat following the 2008 election. Before Obama, Carol Moseley Braun, also from Illinois, served from 1993 to 1999.

In total, there have been six black senators since Reconstruction.

The 2010 field has lacked competitive African-American Senate candidates from the start. One exception, Rep. Kendrick Meek (D) in Florida, has consistently polled behind opponents Marco RubioMarco Antonio RubioOvernight Defense: Senate passes 0B defense bill | 3,000 US troops heading to Afghanistan | Two more Navy officials fired over ship collisions Senate passes 0B defense bill Trump bets base will stick with him on immigration MORE (R) and Gov. Charlie Crist (I) and is not expected to win on Tuesday.

Meanwhile Burris's seat in Illinois will go to either Republican Rep. Mark KirkMark KirkStale, misguided, divisive: minimum wage can't win elections Immigration critics find their champion in Trump Trump's nominee to lead USAID has the right philosophy on international aid MORE or Democrat Alexi Giannoulias. Kirk led the polls by 4 points as of Oct. 31.