The Trump sycophants are unhappy with Ben Sasse because he doesn't always vote with Trump. For example, when Congress voted on a budget that was over $1 trillion in the red, Trump said 'yes', but Sasse voted 'no'. Or when Congress tried to pass that 2-year budget bill Trump wanted which contained a stimulus package larger than the one Obama got in 2009, Sasse voted against that too. Or when Congress was too chickensh!t to do the right thing with the budget and instead passed a 2-week resolution so that they could take their Christmas vacations, Sasse said 'no'. Or when Congress voted to raise the debt ceiling last year, again Sasse voted 'no'.
And for all this, each and every one a Conservative position, Sasse gets trashed by the Trump sycophants because he didn't vote for liberal positions the President wanted.