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TransAlta Corp jumps 8.7% after results

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U.S. midterm elections underway

Nov 8 (Reuters) - Canada's resources-heavy main stock index on Tuesday extended gains to a third straight session as utility and material stocks rose.

At 10:29 a.m. ET (1529 GMT), the Toronto Stock Exchange's S&P/TSX composite index was up 102.69 points, or 0.53%, at 19,648.6.

The index tracked gains in U.S. stocks with midterm elections in the country underway that will determine whether Democrats retain or lose control of Congress.

Forecasts are for a Republican victory, at least in the House of Representatives, and a likely gridlock in Congress, which is considered a positive for stock markets.

"It's a day where such a big potentially monumental news (midterm elections) will be coming out after the markets close, so I don't think too many people are in a hurry to make any big moves ahead of that," said Colin Cieszynski, chief market strategist at SIA Wealth Management.

Meanwhile, shares of TransAlta Corp jumped 8.7% after the company reported better-than-expected third-quarter results and increased its full-year forecast, pushing the utilities index up 1.2%.

The healthcare index, which includes cannabis companies, was the top decliner, falling 1.2% while the energy sector slipped 0.7% as oil prices fell.

Cannabis stocks tend to move on regulatory headlines, including prospects for legalization efforts and odds of friendlier cannabis legislation increase with a Democratic majority.

Among individual companies, Algoma Steel Group dropped 6.0% after missing analysts' second-quarter earnings expectations.

Yamana Gold Inc backed a $4.8 billion takeover bid from Agnico Eagle and Pan American Silver Corp which trumped an offer from South Africa's Gold Fields , paving the way to an all-Canadian deal. Shares of the three Canadian stocks rose between 1.5% and 3.5%.

The materials index added 3.3%. (Reporting by Shashwat Chauhan in Bengaluru; Editing by Sriraj Kalluvila and Vinay Dwivedi)