US stocks closed up Monday, but off their session highs, following the lead of European markets as polls showed support swinging back toward the UK remaining a member of the European Union ahead of a referendum.

    The so-called Brexit vote is set for Thursday and investors have been following it closely for fear that Britain’s exit from Europe’s trading bloc could unsettle global markets.

    The Dow Jones Industrial Average DJIA, +0.73% which had climbed as much as 271 points earlier in the session, closed up 129.71 points, or 0.7%, at 17,804.87.

    The S&P 500 index SPX, +0.58% gained 12.03 points, or 0.6%, to close at 2,083.25. The Nasdaq Composite Index COMP, +0.77% advanced 36.88 points, or 0.8%, to close at 4,837.21.