Depends on the company. Sometimes most of it goes to democrats:
Google for ex - https://www.opensecrets.org/pacs/lookup2.php?strID=C00428623
Microsoft also almost 2x to dems - https://www.opensecrets.org/orgs/summary.php?id=D000000115&l...
Google for ex - https://www.opensecrets.org/pacs/lookup2.php?strID=C00428623
Microsoft also almost 2x to dems - https://www.opensecrets.org/orgs/summary.php?id=D000000115&l...
Note that I'm talking about money from companies (most to Republicans) not the individuals that work for them (most to Democrats).
Labor unions are corporations, and corporations will fight for the corporation's interests. Those interests may align with the interests of their shareholders, but they may not always.