(Updates with fresh details, market reaction and analyst comments)
* TSX up 48.5 points, or 0.32 percent, to 15,388.27
* Nine of the TSX's 10 main groups were higher
By Solarina Ho
TORONTO, May 4 (Reuters) - Canada's main stock index rose broadly on Monday on upbeat investor sentiment, with across-the-board gains led by the materials group and Alimentation Couche-Tard stock.
Convenience store operator Couche-Tard was by far the most influential gainer on the index. Its shares climbed 4.3 percent to C$47.46, recouping a chunk of last week's losses, after the company issued a statement to clarify that the Circle K Corp referenced in a Chapter 11 bankruptcy filing in the United States was not its subsidiary.
Barrick Gold Corp was up 1.1 percent at C$16.08, helped in large part by higher gold prices, which rebounded from six-week lows hit last week. Gold futures rose 1.3 percent to $1,189.4.
Other influential movers on the index included Manulife Financial, which rose 1.09 percent to C$22.34, and Bank of Nova Scotia, which advanced 0.4 percent to C$67.11. The heavily weighted financials group, which make up nearly 35 percent of the index's weight, climbed 0.4 percent.
At 10:45 a.m. ET (1445 GMT), the Toronto Stock Exchange's S&P/TSX composite index rose 48.5 points, or 0.32 percent, to 15,388.27.
Of the index's 10 main groups, nine rose.
"The risk rally has been intact," said Fergal Smith, managing market strategist at Action Economics, noting that market sentiment was generally optimistic.
Investors appeared upbeat that a deal will be reached in Greece, where concerns have heightened over the country's debt crisis, while in the United States, recent data have indicated that the economy appeared to be climbing out of a lackluster first quarter and the Federal Reserve was still prepared to hike rates sometime later this year, even if moves would not be overly aggressive.
"In Canada, the run up in crude oil has also been supportive of the energy sector," Smith said.
After plunging more than 50 percent last year, crude prices have slowly recovered some of their hefty losses. It touched its highest level in 2015 on Monday before retreating.
U.S. crude prices were down 0.9 percent to $58.64, while Brent crude lost 0.5 percent to $66.13.
Energy stocks were down 0.2 percent, with Canadian Natural Resources the biggest drag on the TSX. Shares fell 0.5 percent to C$39.73.
Advancing issues outnumbered declining ones on the TSX by 160 to 82, for a 1.95-to-1 ratio on the upside.
The index was posting three new 52-week highs and no new lows.
Reporting by Solarina Ho; Editing by Ted Botha