So let's focus on Hillary and Bernie, who are truly the odd couple of this race. Like Cher and Bono and a few other celebrities, no surname is needed; both candidates are well-known to the American voter. So I will take the liberty of just using their given names in this post.
Hillary is clearly the odds-on favorite to become the nominee of the Democratic Party. I think it's safe to say that most Democratic women (and men for that matter) yearn for a Hillary candidacy leading to the first female Presidency of the United States. Despite this pioneering role, it is widely recognized that Hillary represents a mainstream candidate who is positioned in the Democratic middle on policy issues. She has been in the national limelight for 25 years as a First Lady, Senator, and Secretary of State. She is intelligent, stolidly articulate, hugely experienced, and we feel we know her ... so much so, in fact, that we are painfully aware of some of the baggage that she and her husband carry.
Bernie represents the far left wing of American politics and proudly labels himself as a "democratic socialist." He is an Independent Senator from Vermont, but is running for the Democratic nomination. Bernie has the kind of street cred that excites populist progressives. He has clearly and unabashedly told us where he stands on domestic and international issues. And he has done so with the passion of a true believer. He is an articulate fighter who will do everything in his power to win the nomination. He will be a formidable presence in any debate.
(I might note that Elizabeth Warren is another person of Bernie's political ilk, who is genuinely distressed by the economic plight of ordinary Americans. Many of us would have loved to see her run, but she chose to not do so. Perhaps in the future ...)
So, here we are. Hillary and Bernie. The odd couple of politics is about to go head-to-head on the issues. Hillary is the favorite, but Bernie may have something to say about that. And he is likely to force Hillary's views to the left, particularly with respect to Wall Street regulation and economic inequality. Regardless, it promises to be an entertaining primary campaign ... and unlike the GOP primary, it will actually address the real struggles faced by Americans.