No, they weren't able to "make" opinions in that way. They sure were able to make more than 50% of the opinions aired on radio, TV, and in print though...
The people with the microphones control the discussion. It can happen that at least half the country plugs their ears and stops listening. But it still is very difficult to have a different discussion from the one that the people with the microphones want to have.
In this day and age every person at their computer have a microphone and a keyboard and potentially an audience. For good or bad. You can have any discussion you like.
Reminds me of this interview with Julian Assange a few days before the elections (in "mainstream media") where he said the "powers, bankers etc." would never let Trump win so Trump would lose. I'd like to hear his comments on that not happening. But maybe he can be forgiven for being paranoid since people are actually after him for real.
EDIT: I'm not ignoring this narrative about the elites but I don't think it's actually true. Trump golfed with the Clintons. They came to his wedding. He was a TV persona. During the elections he intentionally took an adversarial position towards the media to support this narrative (esp. taking on Fox News). From where I'm sitting they are all elite in the same way.
The same mainstream opinion making elites hurt the Clinton campaign by endlessly talking about the re-opening of the e-mail investigation.
Media is definitely opinionated and doesn't offer a diversity of views (which I sometimes see as annoying) but there's some points where it's almost like you'd say that the mainstream elite in education teaches evolution while ignoring the non-mainstream view of creationism.