It’s no secret that exit pollsters have trouble getting representative samples of Hispanic/Latino voters, with sometimes significant consequences, as in 2004 when it was reasonably clear that the national exit polls overstated the Republican share of the Latino vote.
Well, looks like it happened again on November 2, according to a compelling analysis by Gary Segura and Matt Barreto for Latino Decisions. They note several particularly strange exit poll findings:

[T]he exit poll numbers for Sharron Angle in Nevada are mind boggling. Angle, who arguably ran the most offensive campaign against Latino immigrant is estimated to have won 30% of the Latino vote – an 8 percentage point improvement over John McCain in 2008 who won 22% of the Latino vote in Nevada. It is not possible, nor plausible that Angle improved by 8% among Latinos in 2010 given her attacks on Latinos, and Reid’s strong defense of immigration reform. Rather, the Latino Decisions data in the election poll, and our 10 weeks of data from Nevada in our tracking poll both point to very large gains for Democrats in Nevada, and our 90% estimate for Reid matches very close to the vote totals that resulted in a surprise win by Reid that pre-elections polls missed.
In California, the national exit polls would have us believe that Meg Whitman who saw her favorability ratings plummet among Latinos after her contradictory statements supporting Arizona’s SB1070 and her undocumented immigrant housekeeper scandal, also did better among Latinos than John McCain in 2008. In 2008 McCain won an estimated 23% of the California Latino vote, yet the 2010 exit polls suggest Whitman won 30% of the Latino vote, a 7 point improvement? Latino Decisions estimated just 13% for Whitman in 2010.
In Arizona, Jan Brewer, the force behind SB1070 who claimed Mexican immigrants were beheading innocent Arizonans in the southern desert is reported to have won 28% of the Latino vote according to the national exit polls. In contrast Latino Decisions found back in May that Brewer was attracting only 12% of the Latino vote, and that in October our tracking poll estimated 13% vote for Republicans in Arizona, and ultimately only 14% vote for Brewer in 2010, a far cry from 28%.
In these cases, and across the board in 2010, the NEP Latino exit poll results are laughable.

Segura and Baretto discuss glaring examples of poor Latino vote samples for exit poll purposes, and also evaluate possible reasons for the persistent problem, most notably the failure to sample heavily Latino precincts, and the sparse availability of Spanish-language interviewers.
Does this question really matter? Yes, for a very particular reason. The recent lurch of the national Republican Party towards a position of considerable hostility to comprehensive immigration reform was always a gamble that pitted potential gains among white voters against potential losses among Latinos. If someone like Sharron Angle could do as If well among Latinos as John McCain, then it would appear there was little or no marginal political cost for her immigrant-bashing, and perhaps, conservative strategists might conclude, she or future GOP candidates should double-down on the issue and go all Tom Tancredo in an appeal to white voters.
If I were a Republican, I’d be a lot less inclined to be happy about my party’s performance among Latinos in the exit polls, and a lot more interested in making sure the numbers are right before they lead GOP pols in a very unfortunate direction with respect to the country’s fastest growing voter bloc.