(Bloomberg) -- Republicans, newly in charge of theHouse and Senate, begin their campaign to dismantle PPACA with avote this week to ease the law’s requirement that large employers give health insurance tofull-time workers. Under the Patient Protection and Affordable Care Act,companies with 50 or more employees were supposed to offer insurance toanyone working 30 hours or more a week, starting last year. TheRepublican bill would raise that threshold to 40 hours a week,requiring businesses to cover fewer employees. Republicans continue to maintain that the health law must berepealed entirely, even as coverage under the measure grows. Atleast 7.1 million people are enrolled in private plans sold under the lawso far in 2015, and another 9.7 million have been added toMedicaid, the program for low-income people. “At a minimum, we are going to strip out the worst parts,”Sen. John Barrasso, a Wyoming Republican, said on Fox Newstoday. The Republican effort would undo a requirement that the Obamaadministration has already delayed twice on its own. No businesshad to comply until this year, when those with 100 workers or moremust cover at least 70 percent of employees. The mandate won’tapply to smaller employers until 2016. The president will likely threaten to veto legislation tochange the full-time hours threshold before the House is scheduledto vote Jan. 8, a White House official said. The person asked notto be identified because the veto threat isn’t yet official. Setting the threshold for full-time employment at 30 hours hashurt part-time workers, Barrasso said, by encouraging companies tocut workers’ hours. Working hours“It’s hurt people’s take-home pay,” Barrasso said on Fox News.“It made people that work part-time have their hours cut to lessthan 30 hours a week.” Obama threatened to veto similar legislation the Houseconsidered in April. At the time, the White House said the bill“would weaken a provision of the Affordable Care Act that keepsemployers from dropping health insurance coverage and shifting thecost to taxpayers.” The change would increase the deficit by $74 billion over 10years and cause about 1 million people who have coverage now tolose their employer-provided health insurance, the White Housesaid. There is some Democratic support for changing the threshold,as well as some Republican opposition. Senator Joe Donnelly, anIndiana Democrat, will introduce legislation tomorrow mirroring theHouse bill, with Republican Susan Collins of Maine. GOP oppositionYuval Levin, a former White House official under PresidentGeorge W. Bush who is influential among congressional Republicans,wrote in November that the change “would likely put far, far morepeople at risk of having their hours cut than leaving it at 30hours.” Only about 7 percent of employees work 30 to 34 hours perweek, Paul Van de Water, an analyst at the Center on Budget andPolicy Priorities, a Washington research group that advocates forlow-income people. More than 44 percent of employees work 40 to 44hours a week, he said in a report today that criticized thebill. “It’s the present legislation, not health reform, thatthreatens the traditional 40-hour work week the legislation’ssponsors say they want to protect,” he wrote.