25% religious groups:
Pictured are the Quakers, Evangelicals, and Episcopalians; also marching were the Lutherans, Unitarians, and non-denominational churches. The Catholics didn't march, but they were in attendance.
25% politicians and political groups:
As you can see, there were plenty of politicians who sent people to march in the parade.
25% familiar household names:
Pictured are Best Buy, Raytheon, The Home Depot, and Walgreens. Also in attendance were Coca-cola, Pepsi, AAA, Progressive Insurance, esurance, Macy's, Citigroup, Bank of America, and some local businesses and other financial firms.
25% social organizations and bars:
This includes some sort of marching band substitutes:
And not officially part of the parade, but important to have around is some haters:
They had a lot more signs than people (they had between two and three people).
Oh, and top everything with plenty of rainbows: