I think you are correct and I think it is not just the D's that are like this, but also the R's. How else can you explain Trump.
But I think the R's have different problems. Mainly they have backwards social ideas. They also look (whether they actually do or not is another thing) like they don't care about the poor. The R's also have a huge demographic problem. Young people, latinos, Africian Americans, and women on the whole, don't support the republicans. Mostly because of social issues.
1. The Republicans would win with a platform of economic and in a lot of ways foreign policy ideas. Most people support the idea of progressive taxes, but not the way the D's want to make them. People would support reforms to social security and medicare, even if uneasily.
2. They need to get over gay marriage and abortion. These positions are in line with a small (and shrinking) percentage of Americans. Most young Americans support gay marriage. It isn't even a question to them. Yet the R's are trying to overrule the Supreme Court. Spending money to defund planned parenthood is a waste of time and money. Poll it. When people actually understand what 80-90% of what Planned Parenthood does, they support it.
3. They need to find a middle ground on immigration. The idea of closing our country off to anyone else is not how our country came to be. We are a country of immigrants. This is a loser of a position, even if the extreme right loves it.
My caveat is that healthcare is a no win. There isn't a solution that I have seen yet that would satisfy 50% of the country. So many people want free healthcare, but there is no way to fairly pay for that. Socialize medicine is expensive and in many ways creates a system that will dissuade our best and brightest from pursuing medicine. Maybe that is a good thing, but personally I don't think it is. Privatizing healthcare also has many flaws, the first being that without strong regulations, that system will run amok, as all "free" markets do. There are very few examples of a truly free market balancing itself. Usually it corrupts the system with cheaters and swindlers.
I think the Republicans could focus on their core values of economic and tax reform, balanced (or at least limited) budgets, and strong foreign policy, and get more traction with the nation. They lose face when the say that someone has to have a baby, but once that baby is born, the mother shouldn't get food stamps to help feed it. They lose face when their parents came from Cuba to leave oppression and they want to block others from leaving that same oppression.
I think Trump will in the end, be a good thing for the Republicans. They must re-calibrate their party. They need to move past the evangelical vote and look to get new and younger voters. Otherwise they will just be a whiny party who doesn't win.