Stocks Are Having Their Best Week Since April: Live Updates

Wall Street’s rally continued for a fourth day on Thursday, with the S&P 500 gaining about 2 percent and on track for its best weekly showing in nearly seven months, a recovery that has defied predictions that investors would be unsettled by uncertainty in the outcome of the U.S. presidential election.

Thursday’s gains mean the S&P 500 is up 7.4 percent this week, as it rebounds from a loss of 5.6 percent last week. A gain of more than 4.9 percent through Friday would be the benchmark’s best weekly showing since mid-April, when stocks rallied more than 12 percent.

The rally has surprised some market analysts and investors, given the scale of political and economic uncertainties the country continues to face, and some have cautioned that investors’ tolerance of the uncertainty around the election may not last for more than a few days, and concern about a contested election or civil unrest could derail the rally.

“It’s going to be very news-driven and think that we have to expect that there’s going to be a lot of volatility,” said Doug Rivelli, president of the institutional brokerage firm Abel Noser in New York.

For now, however, Wall Street seems to seeing only good news in the possible outcomes. Should Joseph R. Biden Jr. win the presidency, and Republicans retain control of the Senate, the resulting gridlock in Washington will mean few policy surprises to come in the next few years.

If Mr. Biden wins and Democrats carry the Senate, then a surge of government spending aimed at shoring up the economy is also seen as good news for the markets, while expected tax increases and more restrictive regulation are a problem for another day.

That scenario was back on the table on Thursday, as results from Georgia suggested that candidates for both of the state’s Senate races could face a runoff in January, and sectors of the stock market seen as potential winners from a large-scale fiscal push from Washington Democrats fared well.

Shares of two solar companies, Sunnova Energy and Solar Edge, were both up more than 11 percent. Companies that benefit from construction and infrastructure spending such as Terex and United Rentals were up more than 5 percent.

“A Republican Senate takes tax increases off the table, limits more progressive nominees from running the agencies, and takes major restructuring of industries, like health care and energy, off the table. The drawback is that there is less stimulus in 2021. That equation could reverse if the market believes Democrats will retake the Senate,” wrote analysts with Strategas Research.

Another round of stimulus may not wait until a new government is in place. Senator Mitch McConnell of Kentucky, the majority leader, said on Wednesday that reaching a deal on a stimulus bill would be “Job 1” when lawmakers return for the lame-duck congressional session following the elections.

The Federal Reserve left interest rates unchanged and promised to use “its full range of tools to support the U.S. economy,” it said in a policy statement released Thursday, largely repeating its observation that economy and job market are still far behind where they were at the start of the year.

The Fed’s emergency support programs will expire at the end of the year, but analysts are increasingly expecting that the central bank will do more to support the economy if the election outcome leads to a relatively small fiscal stimulus package.

The kind of support the central bank can offer is better for financial markets than it is for unemployed workers and struggling small businesses who don’t directly benefit from it, said William Delwiche, an investment strategist at Baird, a financial firm in Milwaukee.

Mr. Delwiche said a divided government would also probably mean that Jerome H. Powell, the Fed chair, is likely to remain in place: “He’s been the calmest, most reassuring voice through this whole thing, so maybe part of this is the market…