Complex sentence: Reagan eventually got the presidential nomination in 1980 but Schweiker did not become his running mate as the vice presidential nomination went instead to George H.W. Bush and the Reagan-Bush ticket was successful at the subsequent presidential election.
Split into simpler sentences: Reagan eventually got the presidential nomination in 1980 but Schweiker did not become his running mate. The vice presidential nomination went instead to George H.W. Bush, and the Reagan-Bush ticket was successful at the subsequent presidential election.