The battle between congressional Republicans and the White House over the Affordable Care Act is again escalating—in court and on Capitol Hill.

The growth of insurance plans built around small networks of health-care providers is fueling new fights over surprise medical bills, when patients inadvertently get care from out-of-network doctors.

Aetna Inc. and Humana Inc. face resistance from the Justice Department to their proposed $34 billion merger and an uphill battle persuading antitrust enforcers the deal won’t harm competition, according to people familiar with the matter.

With Californians facing the busiest ballot in more than a decade, big spenders are poised to make it one of the most expensive election battles in state history -- already contributing $185 million to fight over everything from sex, drugs and guns to tobacco and taxes.

The Affordable Care Act (ACA) requires individuals who do not qualify for an exception to have minimum essential coverage or pay a tax.

Hillary Clinton formally adopted a more progressive stance on healthcare in a proposal released Saturday, as part of an effort to appease Bernie Sanders and his supporters.