Note: all polling data was provided by the Pew Research Center
As a history major, I find the idea of the Democrats being "socialist" hilarious. Hell, Richard Nixon, a Republican, founded the EPA and Planned Parenthood — if he were alive today he'd be one of the "leftists" that conservatives love complaining about. Speaking of conservatives, they've shifted dramatically to the right, so much so that Reagan himself might have difficulty convincing people he's a conservative. Despite this, and despite the fact that most Americans lean left on climate, health care, and abortion, Republicans continue to control government. You could attribute this to Democrats being bad at winning elections, which they are, but the more you look at the data, the clearer it becomes. The fact is that the vast majority of government and policy is decided by only one demographic.
Let's look at 2016 as an example. Looking at the polling data demographic by demographic, it looks like the 2016 Election should've been a Democratic landslide, but after taking into account as many racial, gender, and educational demographics that I could find, I only found two demographics that consistently and significantly went in favor of Donald Trump: white people without a college degree.
81% of black men voted for Clinton, with 98% of black women voting for her. Both Hispanic men and women only gave Trump 28% of their vote. Not only did Trump lose these groups, but he also lost them by a wide margin. However, when you look at white voters, 54% voted for Trump, with that number jumping to 62% among white men. White women, despite the Republican Party's decidedly conservative take on women's rights, voted in favor of Trump by a margin of 47% compared to the overall female vote of 54% in favor of Clinton.
However, I would argue that race was less of a deciding factor than education. Among whites with a college degree, 55% voted for Clinton, a stark contrast to the overall trend of white voters. Conversely, white voters without a college degree overwhelmingly voted for Trump by a margin of 64% to 28%. However, education was not an indicator across demographics. For example, non-whites with and without a college degree voted for Clinton at 68% and 77% respectively.
The conclusions from the data are obvious: According to the numbers, the Democratic base consists of every racial minority group, educated people, and women, whereas the Republican base consists of white men without college degrees, with white women being more or less being split down the middle. This explains many of the ideas that Republicans have been pushing in recent years.
For example, it explains why they've railed against colleges as politically correct leftist hellscapes. In reality, however, they're just trying to convince people to not go to college. Why? College graduates don't vote Republican. It also explains why they're so against public education, as it's in the Republicans' own best interest to keep the population as stupid as possible so they'll continue to vote them into office.
It also explains their hard stance on immigration. While it has been argued by conservatives that Democrats want immigrants so that they can get more voters, perhaps the opposite is true. Perhaps Republicans want fewer minorities entering the country because, again, minorities don't vote Republican. Republicans have given up on trying to persuade new voters, and have shifted to solidifying their base while attempting to suppress the vote of groups that are a threat to their political power.
Now you might say that it doesn't matter because the Republican base is in the minority and can't win an election all by themselves. However, I would counter by saying that Trump is in office precisely because they won an election by themselves. 64 electoral votes — Wisconsin, Michigan, Pennsylvania, and Ohio — were decided by a combined 100,000 votes. The system is designed in a way where they don't have to win the majority of votes, just win some votes in the right places. In the long run, as the country gets more diverse, this method is unsustainable, but I'm not concerned about the long run. I'm concerned about 2020. Republicans don't need to convert Democrats to win elections, but Democrats have to convert Republicans. The only way for Democrats to regain the presidency in 2020 is to gain votes from white, blue-collar workers.
Unfortunately, no matter how smart you are, you can never convince an idiot that they're stupid.