WASHINGTON (AP) — The Republican establishment’s favorite political machine is adding Colorado to the states where it will be advertising this fall, booking more than $6 million in television time and taking its post-Labor Day media budget to more than $26 million.

The Karl Rove-backed Crossroads GPS on Tuesday ordered TV ads in Colorado starting Sept. 23 and running through Oct. 20 to help Republican Cory Gardner, a House member looking to move his office across Capitol Hill to the Senate. Heavy spending in Colorado has already marked Gardner’s race against first-term Democratic Sen. Mark Udall. Data compiled by the non-partisan Sunlight Foundation shows that Colorado race is approaching the $18 million mark.