se ▁Campbell ▁chose ▁not ▁to ▁run ▁for ▁re - e lection . ▁B rew ing ▁magn ate ▁P ete ▁Co ors ▁opposed ▁Sch af fer . ▁Co ors ▁entered ▁the ▁bitter ▁primary ▁battle ▁after ▁Sch af fer ▁faced ▁down ▁potential ▁cont enders ▁such ▁as ▁David ▁Lin iger , ▁founder ▁of ▁Re Max . ▁The ▁nom ination ▁battle ▁concluded ▁when ▁Co ors ▁won ▁the ▁Republican ▁nom ination ▁over ▁Sch af fer ▁with ▁ 6 1 % ▁of ▁the ▁vote . ▁Co ors ▁went ▁on ▁to ▁lose ▁to ▁Democratic ▁nom ine e ▁Ken ▁Sal azar ▁in ▁the ▁ 2 0 0 4 ▁general ▁election . ▁▁ 2 0 0 8 ▁U . S . ▁Senate ▁election ▁ ▁Sch af fer ▁was ▁the ▁Republican ▁nom ine e ▁for ▁the ▁open ▁seat ▁of ▁ret iring ▁Senator ▁Wayne ▁All ard . ▁He ▁lost ▁to ▁Mark ▁U d all , ▁the ▁Democratic ▁nom ine e . ▁ ▁On ▁May ▁ 9 , ▁ 2 0 0 7 , ▁Sch af fer ▁file d ▁his ▁official ▁statement ▁of ▁candid acy ▁with ▁the ▁Federal ▁E lections ▁Commission . ▁On ▁May ▁ 1 2 , ▁ 2 0 0 7 , ▁he ▁made ▁an ▁official ▁announ cement ▁in ▁B ould er ▁that ▁he ▁would ▁run ▁for ▁the ▁Senate ▁to ▁a ▁group ▁of ▁over ▁ 1 5 0 ▁Republic ans ▁att ending ▁a ▁fund ra ising ▁event . ▁ ▁On ▁September ▁ 2 8 , ▁ 2 0 0 8 , ▁U d all ▁and ▁Sch af fer ▁appeared ▁on ▁Me et ▁the