In an OP-ED for Fox News Newt Gingrich said that Trump’s State Of the Union address should put any thought of a Republican primarying Trump to end.
The 97 percent approval among Republicans, when combined with the 90-10 Trump over Kasich numbers from a recent Emerson College poll of Iowa voters, should end all serious talk of someone challenging him for the Republican nomination in 2020. He may have been an outsider in 2016, but today President Trump is the Republican Party (a fact which makes his relationship with some senators a little difficult).
This is what the GOP Establishment refuses to admit to itself. The bottom line is that Republican Voters stand firmly behind Donald Trump and there is no meaningful section of the Republican voting base that doesn’t want Trump. Primarying him would be an embarrassment for all involved.