McCarthy did not seek reelection in the 1970 Senate election. He sought the Democratic presidential nomination in 1972 but fared poorly in the primaries. He ran in several more races after that but was never elected to another office. He ran as an Independent in the 1976 presidential election and won 0.9% of the popular vote. He was a plaintiff in the landmark campaign finance case Buckley v. Valeo and supported Ronald Reagan in the 1980 presidential election.
mCcarthy diD not sEeK reeleCTion IN the 1970 SEnatE eLectiON. he souGht thE democRAtIc preSidential noMinaTion in 1972 bUt fArEd poorLy in thE priMarieS. he ran in sevEral mOrE rACes aFter that bUt waS neveR ELectED to anoTher OFfIcE. he rAn as aN iNdEpendeNT in thE 1976 presiDeNtIal elECtIoN And won 0.9% oF the popular voTe. HE WAs a pLAintIfF In the lAndMARK cAmpaIGn fiNANCe case buCKley v. vAleo aNd SuPported ronaLd reagaN iN the 1980 pREsideNtIal eLeCtion.