23 CFR § 630.703 - Eligibility.
(a) The State Department of Transportation (DOT) may proceed with a project authorized in accordance with title 23, United States Code:
(1) Without the use of Federal funds; and
(2) In accordance with all procedures and requirements applicable to the project other than those procedures and requirements that limit the State to implementation of a project -
(i) With the aid of Federal funds previously apportioned or allocated to the State; or
(ii) With obligation authority previously allocated to the State.
(b) The FHWA, on the request of a State and execution of a project agreement, may obligate all or a portion of the Federal share of a project authorized to proceed under this section from any category of funds for which the project is eligible.