Republicans make repealing Obamacare 'first order of business'

By Susan Cornwell and Richard Cowan WASHINGTON (Reuters) - President Barack Obama exhorted fellow Democrats on Wednesday to preserve his legacy-defining healthcare law as Republicans launched their long-desired bid to scrap it in what Vice President-elect Mike Pence called the "first order of business" of Donald Trump's administration. The Senate opened debate on a resolution setting in motion the Republican drive to repeal the Democratic-backed 2010 Affordable Care Act, which has helped upwards