For two years, Republicans had been working to correct one of the party’s greatest embarrassments of recent years: the flawed polling that led so many in the party to believe Mitt Romney was on the cusp of victory in 2012. But after dramatically underestimating Democratic turnout in 2012, it was now obvious that the GOP had erred in the other direction in 2014. Their pollsters had understated Republicans’ leads in a number of states, causing the RNC and GOP campaign committees to pour money into places where it wasn’t needed and hold money back from places where it might have made a difference — such as Virginia, where Republican Ed Gillespie lost by less than a percentage point. “It’s just as bad to be wrong by being too conservative,” said Shields. “It’s just as big a mistake to tell a client that you’re only winning by one point when they’re winning by eight. Especially at the party committee level, there are just too many decisions being made … That money can be used elsewhere.” Republicans, it turned out, weren’t the only ones with polling problems: The Democratic internals and public polls also overestimated the Democratic turnout. But the GOP, in particular, had spent months refining its methods just to avoid this problem.
Source: The GOP's numbers problem - Steven Shepard - POLITICO
