What's the matter with Kansas is a great book about that whole issue. Conservatives (Republicans) appeal to dumb people in these types of states on a lot of issues including jobs, giving them false promises and then turning an about-face when the time comes that they're in office.
Republican policies have long benefited the rich, and not the average worker.
I would highly recommend what's the matter with Kansas by Thomas Frank. It is an engaging, informative look at the context around why an entire state of low-income voters voted for policies that were drafted to harm them.
What's the Matter with Kansas?: How Conservatives Won the Heart of America, by Thomas Frank, 2005
The New York Times bestseller, praised as "hilariously funny . . . the only way to understand why so many Americans have decided to vote against their own economic and political interests"