There is little room for common ground when half the country pays no taxes and seems to think the government, ie the half that does pay taxes, should provide them with everything they want, eg, free health care, free food, free housing, free cellphones, free internet, even free contraceptives.
The other half sees the government as an increasingly aggressive enemy, constantly pushing counterproductive and irrational policies, eg the war on energy, pushing unions, affirmative action and all its offshoots, illegal immigration, a crazy foreign policy that seems to favor islamist extremists and undermines allies and the endless scandals and coverups.
Although the media and democrats are constantly whining about hate speech and extremism, any rational person can see that 99% of the hate and vitriol comes from liberals, starting with the president of the country. Liberals are the ones who want to destroy people for having "incorrect" thoughts, who want the speech codes and censorship of ideas they don't like. In the last year or so we had four cases of well-known people in very different fields who were attacked viciously for expressing non-PC ideas, ie the Chic-fil-e guy, the Mozilla CEO, the Duck Dynasty guy and Donald Sterling of the LA Clippers. Three had the temerity to favor traditional marriage, and the fourth was probably tricked into saying some awkward things in a private conversation.
You can't read the sports page without some idiot writer trying to show how morally superior he is by denouncing the name of the Washington Redskins.
In short, some of the disagreement is economic and a lot of it is not. Ordinary people are getting totally fed up with being lectured by a bunch of weirdos and watching their country go down the drain. We are frustrated by the lack of leadership on our side. We have a great leader like Ted Cruz but he is openly undermined by other republicans.
So yes, common ground is hard to find, but don't point fingers at our side. We are past fed up and some incident, like that Bundy ranch invasion, could be the spark that sets off a reaction you won't like.