[muawiyah]

Counting the ranks of the crowd lining the avenue it seems to me that there were at least 120,000 people lining the route from Memorial Bridge to 1600 (the White House).

There are at least 500,000 on the rest of the route up to the Capitol.

[ntnychik]

Thanks for the crowd estimate. WABC is reporting that "thousands" watched the procession.