U.S. stocks are closing mostly higher in quiet trading ahead of the New Year's holiday later this week.
Several European markets fell as Greece headed for elections that could endanger its bailout program.
The Dow Jones industrial average fell 15 points, or 0.1 percent, to 18,038 Monday.
The Standard & Poor's 500 index rose a point, or 0.1 percent, to 2,090. The Nasdaq composite was flat at 4,806.
Trading was light. Volume was about two-thirds of the recent average on the New York Stock Exchange.
Russia's ruble fell 8 percent after a rally last week.
Benchmark U.S. crude dropped $1.12 to $53.61 a barrel in New York.
Bond prices rose. The yield on the 10-year Treasury note fell to 2.21 percent.