Complex sentence: He first established a relationship with Vice President George H. W. Bush, making large campaign contributions to him and heading several critical committees in the Republican Party including being co-chairman of his 1992 re-election committee as well as the chairman of the Republican National Convention.
Split into simpler sentences: He first established a relationship with Vice President George H. W. Bush, making large campaign contributions to him and heading several critical committees in the Republican Party. Lay was co-chairman of Bush's 1992 re-election committee as well as the chairman of the Republican National Convention.