Buoyed by strong quarterly earnings reports, the Standard & Poor's 500 index rallied for a seventh day on Thursday, a five-year peak, Reuters reported. 

The equity market was also boosted by the agreement by Congress to extend the government's borrowing power through mid-May, encouraging signs of recovery in the global economy, solid corporate earnings and seasonal inflows into stocks.

Still, the S&P 500 struggled to climb convincingly above 1,500, a level it surpassed briefly Thursday for the first time since December 2007.

"We are seeing a very broad-based rally, and the ingredients are still in place" for gains to continue, said Steve Goldman, principal at Goldman Management in Short Hills, N.J. "This is the liftoff phase and it's still significant."

If the S&P 500 rises for an eighth day today, it will be its longest winning streak since late 2004, when it enjoyed a nine-day run.