After the last senator had cast his vote on the major immigration overhaul bill that passed the Senate Thursday, there was a long pause in the ornate chamber.

It was unusually packed: almost all senators were at their desks, and the public galleries were full. One section was full of young people wearing blue T-shirts supporting immigration reform: their shirts said "11 Million Dreams." They shushed each other, knowing what was coming. Plainclothes police stood in the aisle, waiting too.