(Updates prices, adds comment)
* Indexes up: Dow 0.32 pct, S&P 0.26 pct, Nasdaq 0.26 pct
By Rodrigo Campos
NEW YORK, Sept 19 (Reuters) - U.S. stocks were rising in early trading on Friday, setting record highs on the Dow and S&P 500 after Scotland's vote to remain in the United Kingdom removed market uncertainty and Alibaba's strong pricing gave support to risk assets.
Unionists' victory in Scotland's vote kept it in the United Kingdom and gave a boost to European stocks, while sterling rose against the euro and the U.S. dollar.
"Disarray in the UK would have had a negative effect, further strengthening the dollar and weakening the commodities complex," said Art Hogan, chief market strategist at Wunderlich Securities in New York.
Regarding Alibaba, Hogan said, "a large, hyped IPO that has gone successfully has a large, positive halo effect on the market."
Alibaba priced its initial public offering at $68 a share, the top end of the expected range, and early indications showed the stock could start trading between $84 and $87.
Shares of Yahoo, which is selling part of its Alibaba stake but will remain a top shareholder, were gaining 1.5 percent at $42.71.
The Dow Jones industrial average was rising 55.69 points, or 0.32 percent, to 17,321.68, the S&P 500 was gaining 5.16 points, or 0.26 percent, to 2,016.52 and the Nasdaq Composite was adding 11.95 points, or 0.26 percent, to 4,605.38.
The largest percentage gainer on the New York Stock Exchange was Dresser-Rand, rising 11.56 percent, while the largest percentage decliner was ITT Educational Services , down 28.50 percent.
Dresser-Rand was gaining 11.9 percent in heavy volume after a report Germany's Siemens plans to offer more than $6.1 billion, or $80 per share, for the U.S. compressor and turbine maker.
ITT Educational Services tumbled to a 19-year low after the for-profit college operator said it received notice indicating the SEC may file an enforcement action against the company due to several loans that were provided to students.
Among the most active stocks on the NYSE were Bank of America, down 0.21 percent to $17.01; General Electric , up 0.44 percent to $26.33; and Pfizer Inc, down 0.36 percent to $30.47.
On the Nasdaq, Microsoft, up 0.8 percent to $47.06, and Apple, down 0.3 percent to $101.46, were among the most actively traded besides Yahoo.
Advancing issues were outnumbering declining ones on the NYSE by 1,775 to 997, for a 1.78-to-1 ratio on the upside; on the Nasdaq, 1,492 issues were rising and 954 falling for a 1.56-to-1 ratio favoring advancers.
The benchmark S&P 500 index was posting 70 new 52-week highs and 3 new lows; the Nasdaq Composite was recording 63 new highs and 31 new lows.
Oracle shares were falling 4.6 percent at $39.65 after Larry Ellison, co-founder and leader for 37 years, stepped aside as chief executive. He will be replaced by co-CEOs Safra Catz and Mark Hurd, raising questions about a job-sharing arrangement that has had mixed records elsewhere. (Reporting by Rodrigo Campos; Editing by Jeffrey Benkoe, Chizu Nomiyama and Nick Zieminski)