Who pays for Obama's transition office expenses?

I am wondering who pays for all of President Elect Obama’s transition expenses: offices, staff, flights, change.gov, etc. Is it the Federal government, the Democratic Party, someone else?

TIA!

–FCOD

Every time there is a transition, Congress appropriates some funds for an Office of the President-Elect, which manages all the transition team stuff. This is authorized under the Presidential Transition Act of 1963.