"There are more coming": House Democrats' headaches are about to get much worse

Progressive groups, emboldened by the Democratic grassroots' extreme dissatisfaction at their party's older establishment, are preparing to go big in their efforts to unseat Democratic lawmakers. Why it matters: Three months into the new Congress, more than half a dozen House Democrats already are facing primary challengers. That number is about to skyrocket. DNC vice chair David Hogg, whose group Leaders We Deserve is spending $20 million to...