Trump Would Lose Badly In A Third-Party Bid, But He Could Take The Republican Down, Too [View all]
Donald Trump is making noise about an independent bid for president. If the Republican National Committee doesnt treat him fairly, Trump says, hell be more likely to launch a third-party run. I dont know if he is at all serious, but I do know two things: History suggests that an independent Trump campaign would crash and fail; polling suggests that even if that happened, Trump could take the Republican candidate down with him.
Trump received 20 percent of the vote in a hypothetical matchup against Democrat Hillary Clinton and Republican Jeb Bush in a newly released ABC News/Washington Post poll. But, if Trump were to run as an independent, his support would likely fade. Since the first Gallup poll in 1936, there have been five independent or third-party campaigns in which a candidate received at least 5 percent of the vote in early polls. All but George Wallace in 1968 ended up with a lower percentage of the vote than they initially garnered, according to Gallup surveys.
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Still, third-party candidates who poll well early dont drop off the map completely. Even John Anderson, whose campaign pretty much collapsed, got more than 5 percent of the vote in 1980. That should be somewhat worrisome to Republicans because Trump would pull most of his support from the GOP standard bearer. In that ABC News/Washington Post survey, Bush dropped from 44 percent without Trump to 30 percent with him; Clinton fell only 4 percentage points (50 percent to 46). Thats a tremendous effect for a third-party candidate.

Only Wallaces bid in 1968 really upended the popular vote. Even Ralph Naders bid in 2000 barely moved the needle because a number of his voters would have backed George W. Bush if Nader werent in the race.
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If Trump does run as an independent, The Donald nightmare may just be beginning for the GOP.
538