U.S. Congressman George Miller, a senior Democrat from California who has long championed education system, labor, health and the protection of natural resources, announced on Monday that he will not seek a 21st term in the House this fall. “This is a great institution and I cannot thank my family and my constituents enough for having given me the honor and privilege of representing my district in Congress these past 40 years,” the 68-year-old Miller said on his website. ““I will leave Congress with a full heart and a crowded plate, because the challenges of our times demand our constant...