Barone on Alito:

The sage political commentator Michael Barone predicts that Alito will be confirmed and that Democrats will not filibuster him either. The reason? The same northeastern Democrats who would be most likely to lead a filibuster because of the abortion issue are also those who have the most to fear from offending Italian-American constituents (as much as 12-14% of the electorate in some northeastern states) from filibustering him.

I would add (for reasons suggested a few days ago) that there may be members of other ethnic groups who may also feel some vicarious enthusiasm for an Italian-American Justice who might further add to these figures in those states.