Stocks slipped from record highs on Friday as lawmakers rushed to bridge differences on additional coronavirus stimulus measures.
The Dow Jones Industrials retreated 96.88 points from Thursday's all-time highs to 30,206.49.
The S&P 500 erased 16.24 points to 3,706.24.
The NASDAQ retreated 16.2 points from Thursday's record closing high, to 12,748.55.
The major averages are on track to post modest gains for the week. The S&P 500 is up 1.6% this week through Thursday's close, heading for its fourth positive week in five. The Dow has gained 0.9% in this period, while the tech-heavy NASDAQ outperformed with a 3.1% rally for the week so far.
The stock market is expected to experience massive volume on Friday as Tesla's historic entry into the S&P 500 is poised to occur based on prices at Friday's close. There will be a rush of activity into the final bell and the S&P 500 will begin trading with Tesla as a member on Monday.
With a market capitalization of more than $600 billion after a 700% rally this year, the electric carmaker will be joining as the seventh-largest company in the index.
Tesla is being added to the benchmark in one fell swoop, marking the largest rebalancing of the S&P 500 in history. It's estimated that passive funds tracking the S&P 500 will need to buy more than $85 billion of Tesla, while selling $85 billion of the rest of the index to make room for it. Shares of Tesla jumped as much as 4% to hit an all-time high on Friday.
Meanwhile, the Tesla inclusion coincides with a quarterly event known as quadruple witching, when options and futures on indexes and equities expire. Many expect Friday to be one of the busiest trading days of the year.
Leaders on Capitol Hill said they are close to an agreement that would provide $900 billion in additional aid. The talks, which have stretched on for months, are up against the wire, with federal funding lapsing at 12:01 a.m. ET on Saturday.
Prices for the 10-Year Treasury were unchanged, keeping yields at Thursday's 0.93%.
Oil prices improved 46 cents to $48.82 U.S. a barrel.
Gold prices backpedaled $2.90 to $1,887.50.