You know him because: He is a U.S. senator from Illinois and assistant majority leader of the Senate.
He would like you to forget: Durbin had to apologize on the Senate floor for remarks he made comparing the techniques used at Guantanamo Bay to those used by the Nazis, the Soviets, and the Khmer Rouge.
Democrats love him because: He is the author of the original DREAM Act, his version allowing undocumented documents a path to legal status if they were brought to the United States as children, finished high school, and were attending college or serving in the military.
Republicans don't like him because: He opposed the Iraq war, one of 23 senators voting against its authorization, and continued to be one of its most vocal critics.
You know him because: He is a former Republican governor of Florida who has endorsed President Obama.
He would like you to forget: As a part of settlement with Talking Heads lead singer David Byrne, Crist had to post a particularly painful video apology to the band for using their rendition of the song "Road to Nowhere" without permission in an ad for his 2010 Senate campaign.
Democrats love him because: While governor, he vocally supported Obama's $780 billion stimulus bill, and also defied his party on issues involving abortion and greenhouse gas standards.
Republicans don't like him because: Republicans accuse Crist of being a political opportunist, as he only left the party in his 2010 Senate campaign to run as an independent when it was clear he would not be able to beat Marco Rubio in the GOP primary.
You know him because: He is a U.S. senator from Massachusetts, the chair of the Senate Committee on Foreign Relations, and the Democrats' 2004 presidential nominee.
He doesn't want you to remember: Kerry was accused of insulting troops with what he later called a "botched joke" he made in 2006: "Education, if you make the most of it, you study hard, you do your homework and you make an effort to be smart, you can do well. And if you don't, you get stuck in Iraq."
Democrats love him because: As a decorated military veteran, Foreign Relations Committee chair, and rumored to be on the list of possible replacements for Secretary of State Hillary Clinton, Kerry can highlight Obama's national security and foreign policy successes.
Republicans don't like him because: Though he initially supported it, Kerry became one of the staunchest critics of the Iraq war. It is also John Kerry who first put Obama on the national stage, tapping him as keynote speaker at 2004's Democratic convention.
You know her because: She is Vice President Joe Biden's wife.
Democrats love her because: She has worked with first lady Michelle Obama to promote support for military families, teaches English full-time at Virginia community college, and even wrote a children's book about her son Beau Biden's deployment to Iraq with the help of his daughter Natalie.
You know him because: He is the vice president of the United States.
He doesn't want you to remember: When running against Obama in the Democratic presidential primary, he called the future president "the first mainstream African-American who is articulate and bright and clean and a nice-looking guy."
Democrats love him because: He was elected to the Senate six times, served as chair of the Senate Committee on Foreign Relations, and used his relationships on the Hill to negotiate a number of key legislative deals passed in the first term of the Obama administration.
Republicans don't like him because: In an interview in May 2012, he said he was "absolutely comfortable" with same-sex marriage, leading to President's Obama's own endorsement of same-sex marriage, which Republicans oppose on their 2012 party platform.
You know him because: He is the president of the United States.
He would like you to forget: In a February 2009 interview with NBC News, he said of the economic recovery, "If I don't have this done in three years, then this going to be a one-term proposition."
Democrats love him because: He repealed "don't ask don't tell," passed a healthcare overhaul law, came out in support of same sex marriage, ended the war in Iraq, rescued the auto industry, and ordered the raid that killed Osama bin Laden.
Republicans don't like him because: Nearing the end of Obama's first term, the unemployment rate has lingered above 8 percent for 42 consecutive months and U.S. debt has ballooned to $16 trillion.
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Updated on 9/6/2012: This article has been updated to include convention speaker Charlie Crist.