The phrase "liberal bastion" refers to a place or location where liberal or progressive ideologies, beliefs, and policies are dominant or well-established. Full definition
Mel and Barbara spent twelve happy years in Tuscaloosa — known as the «Yale of the South,» it was an energetic, liberal bastion of creativity with a fabulous faculty and student body. (thomasmccormick.com)
But during 2016 Democrats appeared to double down on the idea that their populous liberal bastions would be enough to win the White House and the Senate. (businessinsider.com)
In Québec, Lucien Bouchard's secessionist Bloc Québécois won 54 of the province's 75 seats, undermining the old Liberal bastion and destroying Mulroney's fragile Tory coalition. (thecanadianencyclopedia.ca)