The stop in midtown Denver is part of the tree's 28-city tour before arriving at the Capitol.
Sunday's send-off event begins at 2 p.m. at West 68th Avenue and Pecos Street. Santa and Mrs. Claus will be in attendance, helping with ornament decorating and serving hot cocoa and s'mores.
Invited guests include Gov. John Hickenlooper, Sen. Mark Udall, Sen. Michael Bennet, and Miss Colorado, Hannah Porter.
Visitors to the tree are encouraged to show holiday spirit by bringing much needed donations including toys, coats, and non-perishable food.
The tree was harvested from Meeker, Colorado on Nov. 2, hailing from the White River National Forest. The tree is riding in style to the nation's capital on a custom-decorated Mack Pinnacle truck, driven by former Sen. Ben Nighthorse Campbell.
The tree will arrive in Washington, D.C. on Nov. 26. You can follow its journey on twitter @CapitolTree2012.
(KUSA-TV © 2012 Multimedia Holdings Corporation)