A relatively light day of trading on Wall Street ended Thursday with a broad rally for stocks as investors welcomed new jobless benefits data that shows the labor market remains strong.

The S&P 500 rose 1.7%, with roughly 95% of stocks within the benchmark index closing higher. The gains more than made up for the index's losses the previous two days, the latest oscillation in what has been a volatile, holiday-shortened week for stocks.

The Dow Jones Industrial Average rose 1% and the Nasdaq composite gained 2.6%.

Technology stocks, which are down 29% this year, powered much of the rally. Apple...