The man who clubbed U.S. House Speaker Nancy Pelosi's husband in the head with hammer, shouting "Where is Nancy?" after forcing his way into the couple's San Francisco home, faced charges of attempted murder and other felonies a day later.

Police initially declined to offer a motive for Friday's assault on Paul Pelosi, 82, who according to his wife's office underwent surgery for a skull fracture and injuries to his right arm and hands, though doctors expect a full recovery.

But the incident stoked fears about political violence less than two weeks ahead of midterm elections on Nov. 8 that will decide control of the House of Representatives and Senate, coming amid the most vitriolic and polarized U.S. political climate in decades.