Between Palin's lightweight political background, the looming investigation of her abuse of power regarding her ex-brother-in-law, and all the other things swirling around about Palin, lots of people are raising Eagleton and Quayle comparisons. Others turn not to past VP picks, but to Bush's disastrous pick of Harriet Miers for the Supreme Court. But I think what will be the most apt historical comparison is Ferraro.
There is, of course, history being made in both picks. There are plenty of other analogies as well: both are appealing younger women, at least initially; both have some toughness and edge that comes through immediately in their personas; both were able to excite and rally their party's base; both were remarkably inexperienced (Ferraro was in just her sixth year as a junior member of Congress, with no major committee assignments) compared to the vast majority of the previous VP and Presidential nominees.
The biggest similarity, though, is that they both have troubling ethical issues hanging over them: Ferraro and her husband's funky tax returns and Palin's abuse-of-power issues I believe that in the end, the effect on Palin will be exactly the same as it was on Ferraro:
The investigation will play itself out in the media and with the opposition party
She and her party will vigorously defend her, and she will survive, but the initial excitement of her pick will be deflated and lost
She and her running mate will go down to defeat
One of the reasons I wanted to write about Palin was to make the point that while all the work to raise questions about her and define her early is good work, I don't believe that we should over-obsess about her, or spend too much time rushing to chase down every rumor and potentially negative story on her. My view is that her own lack of gravitas and ethical problems will leave her weakened enough that she won't have much of an effect on this race (especially as women swing voters hear more about what a far-out right-winger she is), and that we should keep an eye on the prize: defining John McSame. Ultimately, Presidential elections are determined on the public's views of the candidates running for President, not on the VP pick no matter how weak they are (see Bush/Quayle in 1988). Absent some major new scandal coming out, I'm guessing Palin will weaken the GOP ticket but not be kicked off it.
Update: Okay, folks, I officially admit that I'm starting to re-think this prediction. Every 15 minutes some new damaging piece of info comes forward. She is becoming seriously damaged goods. Maybe the Eagleton comparison will turn out to be right after all.