The battle for Pennslyvania...

And now, the deluge: Thousands upon thousands of campaign operatives and volunteers coming this way; a constant drumbeat of political advertising on the airwaves and Internet; phone banks and robo-calls on overdrive; sold-out hotels and conference rooms; stressed-out police departments managing crowd control at rallies and concerts; swarming national media, some already plying tired rust-belt stereotypes.

All this and more is headed to Pittsburgh, and Pennsylvania, as neck-and-neck Sens. Hillary Rodham Clinton and Barack Obama train their sights on the delegate-rich territory in hopes of clinching the Democratic nomination for president.

The barrage -- "Circus doesn't begin to describe it."