Flip side:  Why is it ok for ny times, la times, fox News, CNN, all media really, to run endorsements, OP- Ed's, and full ok editorial endorsements?

Why can unions do the same? they can collect money, and buy ads, press releases, and more in order to influence politicians and elections.

Free speech. 

So why not people who have companies and collective resources?

Free speech. It is the foundation of the union.