The President's Core Base of Support

Most of the time the president has been in office his approval rating has been in a range of about 41% to 43% based on aggregated poll data by the poll analysis site 538. Today, the president’s approval is 41.6% and disapproval is 53.7%. From that it seemed reasonable to think that his core base of unshakeable supporters is about 41-43%. The logic is that if people still support the president, they are likely solid supporters who would not vote for any democrat in 2020.

Despite that, other indications at least since the 2018 mid-terms kept suggesting his solid support base is somewhat lower.

The Cook Political Report, a low bias, high fact accuracy analysis site, analyzed this question in December of 2018. The CPR wrote:

In this year’s network exit polls, 45 percent approved the job Trump is doing, while 54 percent disapproved. The "strongly approve" number was 31 percent. In the last Fox News poll before the midterm election, 31 percent of registered voters and 33 percent of likely voters strongly approved. The last pre-election NBC News/Wall Street Journal poll pegged his "strongly approve" numbers at 32 percent of registered and 35 percent of likely voters, while the ABC News/Washington Post poll had it a bit lower with 28 percent. So between 28 and 35 percent can be said to be his solid base.

What about Trump’s hard-core opposition? The exit poll showed 46 percent strongly disapproving, while in the Fox News poll it was 43 and 45 percent respectively among registered and likely voters. The NBC/WSJ poll had the numbers a bit larger, with 45 percent of registered voters and 47 percent of likely voters strongly disapproving.

Polling in July and September of this year indicates that about 27-32% of registered voters strongly approve and 45-48% strongly disapprove. That suggests that Trump's solid base hasn't changed much since last December. A different September 2019 poll put the president’s strong approval rating with voters at 28%, with strong disapproval at 45%.

Obviously, support for the president can change over time.  But, if these polls are basically accurate, it is reasonable to think that the president’s core base of unshakeable support right now is about 30% instead of about 42%. If that is correct and holds up for the next 3-4 months, the president will probably need to appeal to a broader swath of the American public than he does now. It isn't clear how or if he can do that, but there will very likely be a major effort to do so. Maybe such an effort already is under way. As of September 2019, about 11% of eligible voters claim to be undecided, so that group could be the key target.