Name ID of Potential Democratic Candidates

Except for Hillary Clinton and Joe Biden, Democrats don't know much about potential 2016 Democratic candidates. Gallup reports:

Massachusetts Sen. Elizabeth Warren, New York Gov. Andrew Cuomo, and O'Malley do not have the long political careers that Biden and Clinton have, and at this point, they are struggling to attain a high profile on the national stage.

• Andrew Cuomo, son of three-term New York Gov. Mario Cuomo, is running for his second term as governor this year after previously being the state's attorney general and Secretary of Housing and Urban Development under President Bill Clinton. Despite that long career and being in a prominent family that includes his brother Chris Cuomo, a CNN news personality, nearly half of Democrats (48%) have never heard of or don't have an opinion of the governor.
• Elizabeth Warren, a first-term senator, was a former Harvard Law professor and served in the Obama administration as a special adviser to the Consumer Financial Protection Bureau. She has been campaigning nationally for Democratic candidates, some of whom are running in traditionally strong Republican states, such as West Virginia and Kentucky. Warren has said that she is touting her populist message to ensure the Democratic agenda succeeds in the next Congress. However, Warren is still far from a household name among Democrats: 57% of Democrats nationally have never heard of or don't have an opinion of the senator.
• Martin O'Malley is finishing his second term as governor of Maryland, having been elected in 2006 after eight years as the mayor of Baltimore. While he counts as a success signing same-sex marriage into state law in 2012, O'Malley has not gained much traction with the American public. The vast majority of Democrats (84%) have neither heard of O'Malley or don't have an opinion of him.