Yes. The Dems lose when they go too far left. A bunch of greedy pubs thought they could have their single issue and flush the party. Lincoln's statement about a house divided works for us, too.
Sam, illegal immigration is one issue amongst a number of issues. It is perhaps the most heated though. The powers that be stiffed folks on the issue of illegal immigration. You can only stiff folks for so long before they react.
The IA issue, isn't even a well focused issue. Immigration is problematic in a number of ways. Right now we have systems set up that totally engulf pre-existing towns with tens of thousands of new immigrants over a decade or so, totally disrupting the status quo. If this were only happening in a few places it wouldn't be so bad. Sadly it's taking place in many areas across the nation.
Then there's the issue of allowing 70,000 Saudi students to enter the nation despite the fact they as Wahabbis, they are some of the most anti-US sects that there are.
I don't want to remain online for the rest of the evening so I'll stop there.
Single issue... even this one issue is multifaceted and it's not the only issue I assure you.