"if Harriet Miers falters or comes up short in any way, the coalition that has elected 3 out of the last 4 Presidents could finally collapse in flurry of recrimination and anger."
I have a different analysis: If the President wisely pulls the plug on this mistaken nomination, or Miers herself throws in the towel, Bush can redeem himself and cement the base by being as bold in nominating an originalist, strict-constructionist, no-foreign-precedent nominee as the Slickmeister was in nominating the far-leftist Ruth "Darth Vader" Ginsburg during his presidency.
Next the Senate Rinos (gang of 14) will filibuster the nomination so this true conservative never makes it to the bench. Face it guys, we don't have the votes to obtain a Priscilla Owens or a Janic Rogers Brown. Furthermore, after being stabbed in the back by his own party the President would be in no position to win such a fight; he would have definitely been weakened by losing the Miers nomination.