(Corrects spelling of name to read "Neal" in paragraph 3 quoting Neal Dietz)
* Investors reallocate as quarter's end nears
* Private-sector job creation in line with expectations
* Cephalon soars after Tuesday bid from Valeant Pharma
* Dow up 0.6 pct, S&P up 0.7 pct, Nasdaq up 0.7 pct (Updates to close, changes byline)
By Rodrigo Campos
NEW YORK, March 30 (Reuters) - U.S. stocks rose on Wednesday with activity dominated by money managers buying recent winners, including energy and small-caps, as the quarter nears its end.
But trading volume remained weak and the S&P 500 failed to hold above 1,330, a level where selling has been clustered in the past month.
"A lot of what you're seeing for the entire week is everybody wanting to be either in or out of whatever they want to show their clients for quarter-end," said Neal Dietz, managing director at Dietz & Lynch Capital in Newburyport, Massachusetts.
The CBOE Volatility Index or VIX, Wall Street's favorite gauge of investor fear, dropped 2.5 percent to close at 17.71, its lowest level since Feb. 18.
Among the S&P 500's biggest gainers on Wednesday were exploration company Cabot Oil & Gas Corp, up 5.3 percent at $53.39. It has risen more than 41 percent this quarter. Chesapeake Energy Corp rose 3.1 percent to $34.33; it is up 32.5 percent this quarter.
Small-caps, which have outdone large-caps in the first quarter, rose sharply, with the Russell 2000 index up 1.2 percent at 839.68, its highest closing level since October 2007. The Russell 2000 is up 7.15 percent for the quarter.
The S&P 500 is up 5.6 percent so far this year.
Unaltered expectations for a healthy number on Friday's labor market data, following a reassuring figure on private payrolls, kept sentiment up.
About 6.8 billion shares traded on the New York Stock Exchange, NYSE Amex and Nasdaq, far below last year's estimated daily average of 8.47 billion.
The Dow Jones industrial average added 71.60 points, or 0.58 percent, to 12,350.61. The Standard & Poor's 500 rose 8.82 points, or 0.67 percent, to 1,328.26. The Nasdaq Composite gained 19.90 points, or 0.72 percent, to 2,776.79.
In the latest deal news, Canadian drugmaker Valeant Pharmaceuticals International made an unsolicited bid to buy Cephalon Inc for $5.7 billion, driving Cephalon's stock up 28.4 percent to $75.44 while Valeant's U.S.-listed shares shot up 12.8 percent to $50.08.
The deal pushed the NYSEArca biotech index up 2.9 percent.
The U.S. labor market showed further recovery in March as private-sector employers added jobs while planned layoffs fell, according to separate reports on Wednesday.
The ADP report on private-sector jobs, which may not be a dependable indicator of the government's broader jobs report due on Friday, showed 201,000 jobs being created. That kept expectations intact for the Labor Department's report.
Advancing stocks outnumbered declining ones on the NYSE by 2,191 to 811, while on the Nasdaq, more than two stocks rose for every one that fell. (Reporting by Rodrigo Campos; Editing by Jan Paschal)