Uncertainty surrounding the U.S. presidential election, expectations for higher interest rates and weak corporate earnings will keep U.S. stocks from advancing much in the fourth quarter, according to strategists in a Reuters poll.

 

The benchmark S&P 500 index .SPX will end the year at 2,173, according to the median forecast of 40 strategists polled by Reuters over the past week. That would be up slightly from Monday's finish of 2,161.2 and a gain of about 6 percent for 2016.

 

Between July and August, the index hit a series of all-time highs, with the record close now standing at 2,190.15. But strategists expect the S&P to surpass that in 2017, notching up a yearly gain of about 6 percent to 2,310.

 

Strategists were more optimistic than they were in July, shortly after Britain's vote to leave the European Union.

 

But the race for the White House between Democrat Hillary Clinton and Republican Donald Trump will take on greater importance as the Nov. 8 vote approaches and should cause more volatility, especially in sectors like health insurance, pharmaceuticals and energy, strategists said.

 

In the poll, respondents overwhelmingly viewed a Clinton victory as more positive than a Trump win for U.S. stocks, at least until year-end. Indeed, a perceived win by Clinton in the first presidential debate of the season on Sept. 26 helped support U.S. equities the following day.

 

"One of the principal factors holding stocks back is policy uncertainty," said Brad McMillan, chief investment officer for Commonwealth Financial in Waltham, Massachusetts. "Should Mrs. Clinton win, for better or worse, markets think they know what she will do."

 

More strategists than not see a high likelihood of a 10 percent or more correction in the U.S. market over the next 12 months, and they view continued weak earnings and more Federal Reserve rate hikes than expected as among the biggest risks to global stocks over the coming year.

 

"History says the first one or two Fed rate hikes do not blow up markets," said Tobias Levkovich, chief U.S. equity strategist at Citigroup in New York. "Then you get people who say ... this time is different."

 

The Fed has held off on raising rates so far this year after doing so in December for the first time since 2006. Traders see a greater than 60 percent chance of another hike this December.

 

Companies' earnings will also weigh on the market, with forecasts continuing to weaken.

 

Analysts expect third-quarter reports, which are set for release in the coming weeks, to show an average earnings decline of 0.5 percent from a year earlier, according to Thomson Reuters data. This would extend the S&P 500's profit recession to the fifth straight quarter.

 

The Dow Jones industrial average will end 2016 at 18,455, showing gains of 6 percent from 2015's close and 1 percent from Monday's finish, the Reuters poll showed.

 

(Poll data: EQUITYPOLL1)