Do you remember Maslow's Hierarchy of Needs from school?
In essence, you must have certain needs met before other things become important to you. In order to care about other people, your survival needs must be met. If you have food and shelter and safety, you can start forming relationships. This continues on up the chain, through families and communities and countries. When our needs are met, we can begin considering the world around us in new ways beyond just, "Where is my next meal? What am I competing with other people/communities/countries to get?"
Now think about this in line with living in a depressed economy in a small town in America.
When you don't know where your next meal, your next tank of gas, or your next rent/mortgage payment is going to come from, it can be awfully hard to think about social issues and social concerns that don't affect you directly or that aren't part of your community.
In order to respect opposing points of view, you have to be in a place where you can look at the person you don't agree with and still see them as a person with needs and rights. It's hard to pay attention to someone else's needs when you're hurting unless that person's needs are the same as yours. If something prevents you from relating to that person -- they're homosexual, they're an illegal immigrant, they're a different religion, whatever it is -- then you have a hard time realizing they're in the same place you are when it comes down to basic needs.
For decades the Republican party has seized upon these fundamental differences of opinion and experience and turned them into their talking points. They dominate conservative talk radio with mutual affirmation. They relentlessly equate the right to bear arms with the ability to defend oneself from tyranny from a government that doesn't understand you: the government is screwing you over, but this half of the government at least wants you to have a gun. They have shrewdly and successfully turned the central anger and frustration people have with the government into a "win" for them. In the grand scheme of political success, it is an impressive victory. It allows them to point to the liberal agenda and say, "look, the few things we do give you, they want to take that away."
I have a crazy theory that the bitter partisanship over social issues in this country would lessen if more people felt secure in their own lives. It might allow them to take a step back and realize that even though they don't agree with everybody else, they might not feel so strongly about legislating away other people's rights to be different. Having a steady job and health insurance won't turn rural blue-collar workers into an army of gay rights activists, or a lobby in favor of immigration reform. But it might give them the personal breathing room to be able to accept different people in America as simply Americans, rather than people with whom they must compete for the meager scraps their elected officials bestow upon them.
This is the core of what Obama's all about: understanding what we have in common. I think it's a key to what Obama's saying on the subject of bitterness and factors that influence voting, however clumsy you might consider the use of the word "cling" in that context.
Coming back to Maslow and Obama's view of America: on March 18th, Obama asked us for help in perfecting the union. Maslow tells us that our quest is toward self-actualization, but that the journey is dependent upon maintaining the current level in the hierarchy. We cannot achieve self-actualization or a perfect union in one fell swoop, through the act of electing one individual. But we can work to cement ourselves in a level of the hierarchy that gives us room to grow; we can try to be better neighbors and friends and family members, and in doing so, even if we sometimes take a step back, we can remember what it felt like to be in that higher place and move toward it again.
The cure for bitterness -- the only cure for bitterness -- is hope. And the actualization of hope requires us to take chances, and to work hard.