This is actually surprisingly difficult. As is said in the podcast, ideology (a continuum from liberal to conservative) and party affiliation (e.g., Democrat, Republican) are two different things, and although they do go together sometimes, they can also diverge. Determining whether a person is part of the Democratic or Republican base has to be more than simply determining if they're liberal or conservative. They also have to align with party activities and causes, and have a voting track record aligning with the party.
I highly recommend giving the podcast a listen.
In the podcast, they also talk about the parties more generally and even highlight some of the things Republicans and Democrats can agree on - specifically that the President should stay off of Twitter. So U.S. Representative Mike Quigley's COVFEFE (Communications Over Various Feeds Electronically for Engagement) Act is well-timed:
This bill codifies vital guidance from the National Archives by amending the Presidential Records Act to include the term “social media” as a documentary material, ensuring additional preservation of presidential communication and statements while promoting government accountability and transparency.
“In order to maintain public trust in government, elected officials must answer for what they do and say; this includes 140-character tweets,” said Rep. Quigley. “President Trump’s frequent, unfiltered use of his personal Twitter account as a means of official communication is unprecedented. If the President is going to take to social media to make sudden public policy proclamations, we must ensure that these statements are documented and preserved for future reference. Tweets are powerful, and the President must be held accountable for every post.”
In 2014, the National Archives released guidance stating its belief that social media merits historical recording. President Trump’s unprecedented use of Twitter calls particular attention to this concern. When referencing the use of social media, White House Press Secretary Sean Spicer has said, “The president is president of the United States so they are considered official statements by the president of the United States.”