Our Supreme Court has decided that corporations spending money[3], even in politics[4], is speech as well.
The O'Brien test[5] is generally used to tell whether a law encroaches on 1A rights.
[0]: https://en.wikipedia.org/wiki/Texas_v._Johnson [1]: http://joshblackman.com/blog/2018/07/10/doj-second-amendment... [2]: http://www.cs.cmu.edu/~dst/raisethefist/archive/abi.htm [3]: https://www.freedomforuminstitute.org/first-amendment-center... [4]: http://www.scotusblog.com/case-files/cases/citizens-united-v... [5]: http://law2.umkc.edu/faculty/projects/ftrials/conlaw/obrient...
Banning political advertising is just a play to strengthen incumbents and hurt new comers. I also think it's morally wrong. It's "you should not try to influence others by yourself - only government approved channels are ok and maybe you will get a minute a day if you're already visible in the polls" kind of law. It's censorship reminding me of Soviet days. Europe is terrible when it comes to freedom of expression. Blasphemy laws are another example of prosecuting speech some groups don't like.