The Democratic Party is neoliberal by every imaginable definition of the term, and so-called "classical liberalism" was abandoned with the onset of WW2. Which liberalism are you referring to?
In the conservative/liberal spectrum of the US, the Democratic party is left-leaning centrist. There is no mainstream "liberal" party in the US.
But aside from that, what I also mean is that the Democratic party has members from all across the political spectrum. There are even extremely conservative Democrats. So, however you define "liberal", it is not accurate to consider "democrat" and "liberal" as being essentially synonymous.
People seem to falsely equate liberal with leftwing. They are very different. In fact no one hates liberals quite like left wingers. Democrats are liberal, not leftist (though they have adopted some leftist bits)
Liberals (and neoliberals) want everything controlled by markets. The government should butt out and collect no more taxes than is reasonably needed to set and enforce the market rules. Everything else should be private. Not too different from libertarians except that they have more common sense.
Leftists want the government to have an opinion and directly act and spend money in order to achieve specific outcomes. If there are many homeless, don't try to influence the market to increase supply or drop price, just directly go and build houses. If we need clean energy, don't dick about with carbon credits and incentives, just go and hire some engineers and build wind turbines.
