i have a list of bookmarks for this, so take your pick of any of the following:
general, not ideology-specific
- Jacobin
- The Nation (US-oriented)
- Democracy Now
- Tribune (UK-oriented)
- Open Democracy (mostly UK-oriented, i believe)
- The Maple (Canada-oriented)
- The Intercept
- Truthdig
- Truthout
- Jewish Currents (Jewish-oriented, obviously)
ideology-specific
- Left Voice (Trotskyist)
- Industrial Worker (anarcho-syndicalist/syndicalist, published by the IWW)
- It's Going Down (Anarchist)
longer form or more irregular
- Current Affairs
- Dissent Magazine
- In These Times
- Spring Magazine (Canada-oriented)
- Protean Magazine