LOUISVILLE, Ky. — The next Congress will begin work immediately next year toward repealing President Barack Obama’s health care law but delay the changes as Republicans try to come up with an alternative, Senate Majority Leader Mitch McConnell said Saturday.The Kentucky Republican insisted that some 20 million Americans who have health care through the six-year-old law will not lose coverage, though the likely upheaval in the insurance industry suggests many could.Asked about the Senate’s timetable to scrap the law, McConnell said: “We’re going to move to it after we go back in the first week in January.”But during a speech in his hometown of Louisville, the senator cautioned patience from the law’s critics as Republicans create an alternative.“You can’t just snap your fingers and go from where we are today to where we’re headed,” McConnell told a crowd at the Kentucky Farm Bureau’s annual meeting. “This has to be done carefully. It has to be done in a phased-in way over a period of time.”Republicans have been unable to agree on an alternative since the law’s enactment in 2010, but now must produce a replacement if they scrap the law. President-elect Donald Trump says he would like to keep major elements of the law — allowing children to remain on their parents’ plans until age 26 and ensuring companies don’t deny coverage for pre-existing conditions. But it’s unclear how a new version of the law could force insurance companies to provide the latter coverage.