"They're about to detonate a nuclear bomb on themselves," said one savvy House Democratic strategist following Tuesday's primaries. "If Ted Cruz is your back up plan, you're screwed," the strategist gleefully added. Maybe that's true, and maybe it's not. But now that it's extremely likely that the Republican Party will nominate Donald Trump or Ted Cruz, congressional Republicans are entering uncharted and potentially dangerous territory. So many assumptions have been wrong this cycle that it's difficult to be definitive about another: that the House majority won't be in play in 2016. Republicans are sitting on their largest majority since 1928 - 247 seats to 188 - meaning Democrats would need to pick up 30 seats, a daunting challenge given the GOP's immense redistricting advantage and the vaporization of swing districts. But all cycle, Democrats have daydreamed about Republicans nominating an extremely polarizing presidential candidate, and suddenly it's almost certain they will get their wish. A Trump or Cruz nomination wouldn't guarantee a down-ballot disaster for the GOP, but operatives on both sides admit it would inject much more uncertainty into

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