There is simply is no downside to the GOP presidential field, whether real or imagined. The Boston Globe:
According to a [Suffolk University poll] of likely Granite State primary voters, if Romney was added to crowd of GOP presidential hopefuls, he would lead the field with 31 percent of the vote — more than double that of current frontrunner Donald Trump.
My dreams of a Trump nomination are equaled in quantitative wetness only by the spectre of a Romney nomination. Be still my … heart?
I very much miss Mr. Romney's unique political skill of obliviously alienating ever-larger blocs of American voters. There is that, there is definitely that. But more than that is that the Trump-Cruz-wing primates of the rib-scratching Republican base would go absolutely bananas were another "RINO" to seize, with the aid of opposable thumbs, the nomination. Their furious partisan grooming and animated vowel screeching would present an even greater show on earth than that of Trump's slide to worse-than-Goldwater numbers.
There's just no downside here. Mitt Romney is the best the GOP has to offer — and he was the worst presidential candidate in modern political history. The Republican field is that bleak.