The House of Representatives is set to vote on a GOP plan to repeal and replace Obamacare early Thursday afternoon. The measure is expected to pass with a small cushion above the 51-votes needed to win a bare majority.

Republican leaders can afford to lose only 22 votes from their party and still have the measure past. Polls of GOP members indicate that the opposition, once strong enough to stop the bill, has dwindled to 15. 

After weeks of grueling negotiations, House Speaker Paul Ryan of Wisconsin received a standing ovation after addressing the GOP conference Thursday morning.

A critical change to win over GOP moderates in the past 24 hours was President Donald Trump's agreement to provide an additional $8 billion to some states to reduce costs for covering individuals with pre-existing conditions.

On Wednesday Rep. Fred Upton, R-Mich., and Rep. Billy Long, R-Missouri, dropped their opposition and agreed to vote for the bill after winning Trump's backing for their amendment providing for an additional $8 billion over five years to help states that have waivers allow insurers impose higher premiums on individuals with pre-existing conditions. Under Obamacare charging those individuals more is forbidden.

Another new amendment from Rep. Tom MacArthur of New York that helped keep conservatives' support would let states apply for waivers from some of the health law's insurance requirements.

At the last minute Ryan pulled the original health care overhaul from floor consideration in March because it lacked the votes to pass

Should the legislation be enacted, the biggest beneficiaries among public companies are likely to be the largest health insurers, including Anthem (ANTM - Get Report) , UnitedHealth (UNH - Get Report) , Cigna (CI - Get Report) and Humana (HUM - Get Report) .

Hospital stocks such as Tenet Healthcare (THC - Get Report) , Community Health (CYH - Get Report) , HCA (HCA - Get Report) and LifePoint Hospitals (LPNT) are likely to suffer from cuts to healthcare providers' revenue.