Democratic candidates for public office are now commonly called “liberals.”
But it isn't that simple. Their views vary more than Republicans, and they vote together as a party less frequently.
We see the term “moderate,” but mostly when describing some Republicans. Democrats can be moderate or conservative. What has changed is not the number of conservative Democrats, but our acknowledgment that they exist.
Candidates are not automatically liberal if they are not conservative. Prime examples are in the current Wisconsin Supreme Court and State Superintendent of Public Instruction races.
Our democracy was founded on the principle of one person, one vote. In 2010 our U.S. Supreme Court (the Roberts Court, so-named after Chief Justice, then and now, John Roberts, a George W. Bush appointee) voted to allow unlimited campaign donations by corporations and special interest groups ("Citizens United" decision).
The two “liberal” candidates in our state Supreme Court and State Superintendent races have received one-third and one-tenth respectively, the amount of independent expenditure money from special interest groups compared to their two “conservative” opponents. This money allows candidates to buy more and varied forms of communication with voters which is known to generally swing elections.