Angered by White House decisions on everything from greenhouse gases to car dealerships, congressional Democrats from rural districts are threatening to revolt against parts of President Barack Obama’s ambitious first-year agenda. “They don’t get rural America,” said Rep. Dennis Cardoza, a Democrat who represents California’s agriculture-rich Central Valley. “They form their views of the world in large cities.” A rural revolt could hamper the administration’s ability to pass climate change and health care legislation before the August recess. In the House, rural Democrats threaten to marshal nearly 50 votes against the climate and energy bill backed by the administration.