I always pause at first when asked for "proof' by liberals, since their conception of proof is totally different than that of conservatives. I forgot where I heard it (after the 2016 election, but some things are better proved by the "pudding" than anybody's biased reports.In this case it makes sense. The media has an approval rating of about 10%. Near zero with Republicans who see the media as the enemy (as Trump himself said). The polls are just more of this media that Republicans don't trust. The proof in the pudding showed up in the 2016 elections where polls were showing Hillary to win.All this probably won't go over with liberals though, who expect to see a Gallup, NBC, or Bloomberg report.
Liberal Pollsters & Media Collude To Skew Polls