Many of the statistical analyses of whether or not Ross Perot really was responsible for George H.W. Bush’s loss of the presidency ignore the timing of Perot’s moves into, out of, and back into the race.
When Perot, who died Tuesday at age 89, first entered the race, Bush was well ahead of Bill Clinton in the polls. Perot entered, rhetorical guns blazing at Bush, tearing down the incumbent so Clinton didn’t need to muddy himself. A lot of “soft” Bush voters had trouble imagining themselves voting for the draft-dodging, promiscuous, overly “hip” Clinton, but Perot provided a way station for people to drop off Bush without going all the way to Slick Willie’s camp. Perot pulled mostly from Bush then, and only a little from Clinton, but did so well at it that Perot actually shot to the top of the polls.
Then Perot melted down. He acted like a one-man loony tune, on multiple fronts. In particular, Perot showed a tendency toward paranoia, asking campaign volunteers to sign loyalty oaths, worrying that the New Black Panthers would assassinate him because he made the mistake of referring to blacks as “you people,” and (allegedly) sending aides to accuse co-campaign manager Ed Rollins of being a CIA-tied plant on behalf of the Bush team.
As Perot sank in the polls, Clinton rose. When Perot dropped out of the race in July, Clinton reaped most of the benefit, and took a 19-point polling lead over Bush.
Perot wasn’t done, though. By late September, people began having second thoughts about Clinton. This is normal: Voters have a habit, as campaigns reach the post-Labor Day home stretch, of getting nervous about candidates reasonably new to the national scene. Clinton’s support began to slip. That’s when Perot re-entered the race, again providing a stopping-off point, this time to keep tentative but nervous Clinton leaners from moving all the way back to Bush. His entry halted Bush’s new momentum for weeks — and, of course, Perot spent far more time criticizing Bush than Clinton, again driving Bush’s negatives up.
Perot regained momentum himself. Too much momentum. As he rose from 10% to 20% in the polls, Clinton dropped from 51% to 41%. That’s when Perot torpedoed himself one more time — again, to Clinton’s benefit and Bush’s detriment. Perot started spouting bizarre nonsense about Bush’s people supposedly infiltrating his daughter’s wedding. That halted Perot’s own mojo, and froze the race in place with Clinton still ahead.
At every step, Perot’s political permutations, whether by design or happenstance, helped Clinton more than Bush, or hurt Bush more than Clinton. His rhetoric overwhelmingly hurt Bush.
It’s fair to say that without Perot’s participation, Bush would have had a far better chance of being reelected.

