Wall Street’s three major indexes tallied record closing highs on Friday with broad gains across sectors as a long-awaited tax bill that would cut corporate tax rates looked like it would win enough support from lawmakers to pass.

Republicans were expected to release final details of their plan late on Friday, with decisive votes planned for next week after lawmakers who had previously criticized the bill started to voice their support.

Republican Senator Bob Corker joined Senator Marco Rubio in signaling support in the late afternoon. Rubio had criticized the initial proposal, saying it did not give enough tax relief to working families, while Corker, had expressed concerned about the bill’s impact on the federal deficit.

The bill is expected to drop corporate tax rates to 21 percent from 35 percent and some investors are betting that companies will put most of the savings toward a boost in shareholder payouts.

However, as the tax package has evolved, it has tilted increasingly toward benefiting businesses and the wealthy, a trend that concerned some lawmakers.

The S&P 500 and the Dow closed higher for the fourth week in a row, while the Nasdaq saw its first weekly gain out of three.

The S&P 500’s Energy index was the only one of its 11 majors in the red with a 0.03-percent dip. Technology and Healthcare indexes led the advance with 1.24 and 1.17 percent gains, respectively.

The S&P financial index closed up 1.04 percent, paring earlier gains. Banks are one of the greatest beneficiaries of tax reform.

The S&P consumer staples index rose 1.12 percent. Costco was its largest percentage gainer, up 3.7 percent, after the retailer reported upbeat results.

CSX fell 7.6 percent. The railroad said its Chief Executive Hunter Harrison was taking medical leave amid its controversial turnaround plan.

Quadruple witching, the simultaneous expiration of options and futures contracts for stocks and indexes, raised volume to 10.7 billion shares, well above the 6.73 billion share average over the past 20 trading days, and the highest since a year ago.