U.S. stocks rose on Monday as energy shares gained with oil prices and as Apple jumped due to rival Samsung Electronics' worsening smartphone recall crisis.
Aiding the advance, polls showed Democrat Hillary Clinton's lead widening in the U.S. presidential race following further turmoil in Republican Donald Trump's campaign over the weekend and a late Sunday debate between the candidates.
Clinton is viewed as more positive for stocks partly because her positions are well known, Wall Street strategists have said.
Apple's stock jumped 1.7 percent to $116.05 and hit a high not seen since December after Samsung Electronics Co Ltd suspended production of its flagship Galaxy Note 7 smartphones following reports of fires in replacement devices.
"Samsung's woes being Apple's gains helped with that stock a lot," said Peter Tuz, president of Chase Investment Counsel in Charlottesville, Virginia.
"The (presidential) debate further set in stone the idea that Hillary Clinton is the likely winner and that you get the market you know rather than the market you don't know."
Oil prices rose, lifting energy shares, after Russia said it was ready to join OPEC in curbing crude output and Algeria's oil minister said he expected similar commitments from other non-OPEC producers.
The Dow Jones industrial average was up 88.55 points, or 0.49 percent, to 18,329.04, the S&P 500 gained 9.92 points, or 0.46 percent, to 2,163.66 and the Nasdaq Composite added 36.27 points, or 0.69 percent, to 5,328.67.
The energy index was up 1.5 percent. Exxon and Chevron were among the top influences on the S&P and the Dow, along with Apple.
An NBC News/Wall Street Journal poll on Monday showed Clinton increasing the recent lead she has held over Trump.
Mylan rose 8.2 percent to $38.87 after the drugmaker late on Friday said it would pay $465 million to settle questions over whether it underpaid U.S. government healthcare programs by misclassifying its EpiPen emergency allergy treatment.
Twitter Inc shares ended down 11.5 percent but pared losses late after a Reuters report, citing people familiar with the matter, that Salesforce.com Inc is still deliberating whether it should make an offer for Twitter.
This week marks the start of the roughly month-long corporate earnings season, which could help determine investors' moods going into the Nov. 8 vote. Some investors hope that the period will mark an end to the year-long U.S. profit recession. Results from Alcoa are due Tuesday after the close.
Trading was light because of the U.S. Columbus Day holiday. The bond market was closed.
About 5.2 billion shares changed hands on U.S. exchanges, below the 6.9 billion daily average for the past 20 trading days, according to Thomson Reuters data.
Advancing issues outnumbered declining ones on the NYSE by a 2.56-to-1 ratio; on Nasdaq, a 2.36-to-1 ratio favored advancers.
The S&P 500 posted 27 new 52-week highs and 2 new lows; the Nasdaq Composite recorded 133 new highs and 35 new lows.
(Additional reporting by Yashaswini Swamynathan in Bengaluru; Editing by Anil D'Silva and Nick Zieminski)