(CNN) Stop me if you've heard this one: Mitt Romney has emerged as the face of the Republican resistance to President Donald Trump.

Unless you've not been paying any attention, literally, to politics over the past four years, you'd have stopped me. Because Romney, the 2012 Republican nominee and now a senator from Utah, has repeatedly spoken out against Trump's most egregious acts and statements -- only to retreat amid a verbal barrage of criticism from the President and his supporters.

Romney is at it again following Trump's imploring of Ukraine and China to look into debunked allegations of corruption directed at Joe Biden and his son, Hunter.

"By all appearances, the President's brazen and unprecedented appeal to China and to Ukraine to investigate Joe Biden is wrong and appalling," Romney said Friday . Which, of course, prompted Trump to respond -- calling the Utah Republican a "pompous ass" who had been "begging" to be his secretary of state when Trump took office.

Again, this stuff is par for the course between these two men. So what's different this time around -- if anything?

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