The market will rally next week if the Republicans take back the Senate during the midterm elections Nov. 4, and two sectors in particular will benefit, ConvergEx Group chief market strategist Nick Colas told CNBC Thursday.
With polls showing the GOP in the lead, Colas would buy energy and financials ahead of Election Day. That's because a recent survey by his firm of its clients and partners found there was "overwhelming confidence" those sectors would do well if the Republicans became the Senate majority.
Of the 186 market participants surveyed, 90 percent believed energy would benefit and 88 percent thought financials would.
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"Financials have been hard hit by regulations that drive down their returns, and energy has similar problems getting new projects approved," Colas explained.
However, most important, he pointed out, was respondents said nine of the 10 sectors would go up on a Republican victory. Health care would be the only sector that would not benefit, according to the ConvergEx poll.
While there have been many years of "excellent returns" in the market, that has been thanks to the Federal Reserve's bond-buying program, Colas told CNBC's "Street Signs." The central bank announced Wednesday it was ending that program, known as quantitative easing.
"Now that the Fed has ended QE … we do have to look to Congress and the president for any incremental catalyst coming out of Washington. The good news there is nobody expects anything. Approval ratings are in the basement. Any positive would be a positive," he said.
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That means even if the Democrats maintain their majority, Colas doesn't believe stocks will take a hit because the market is already expecting the status quo.
"Expectations are already so low; I don't see the market cratering with that result at all," he said.
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Jeff Hirsch, editor-in-chief of the Stock Trader's Almanac, isn't convinced Republicans will take back the Senate.
That said, if the GOP does win it will be the "best situation for the market," he said. "Democratic presidents, Republican Congresses [have had a] 19.5 percent average return since 1949."
—CNBC's Stefanie Kratter contributed to this report.