They came. They saw. They protested.

Yet it remains to be seen whether the demonstration Saturday in the nation's capital, against what protesters view as out-of-control spending by an expanding federal government, will conquer Washington.

The tens of thousands of protesters marched to the U.S. Capitol chanting various slogans and waving posters that voiced a rather broad array of grievances against big government and the leaders, particularly President Obama, who the protesters blame for its size and scope...