Republicans year after year show up at the polls. That can't always be said about Democrats. Yet when motivated, they clearly outnumber their counterparts and will come out of the woodwork for change. Just as they did for Obama and will now that they had a taste of this corruption. It's nieve" to think any different or that Trump picked up any new voters since elected. Nothing even close to the number he's lost since taking a chance on the idiot. And he had the help of Russia in 2016. That's still going on, but not to the extent it was. Rich Democrats like Tom Steyer have spent millions organizing and motivating the non-voters and younger millennials to show up at the polls in 2020. There are no new Trump supporters to recruit and motivate. That gene pool is virtually empty. Let's see who the coal miners, farmers and the like show up to vote for this time around after all the broken promises were unfulfilled. That is if he makes it to 2020. We still have a year of more scandal and exposure to uncover such as getting his taxes exposed. Though personally, I'd be happier just voting him out in a year. The delay in the impeachment hearing is nothing but a blessing. He thinks he's smarter than Pelosi. He's not. Only more corrupt. I'm going to guess more stressful emergency hospital visits in the very near future. You know the old saying...pressure broke the pipe. It's going to be a fun time these next 12 months watching him squirm and eventually crack.
Truth
You nailed it-Trump needs a whole bunch of new voters in 2020 to win and the protest votes he received last election will either stay home or vote against him this year.
2016 factors
1. Outside help from foreign country and Wikileaks's
2. A historically unpopular candidate in Hillary
3. Won Michigan/Wisconsin/Pennsylvania by a combined 77,000 votes
4. Lost popular vote by 3.5 million
And now that trump has proven he's way in over his head and incapable of performing the job trumptards think he will win in a landslide.
The mere fact that 54% of Americans currently feel he should be impeached and removed from office tells the story on how the election will go.
Not to mention that R's are losing races in places like Kentucky and Louisiana and got slaughtered in the 2018 mid terms.