The has been in a 16 percent range for the better part of two years, pingponging between 1,810 and 2,135. But the November election could break out the market — one way or another.
"If you get someone like a Republican nominee coming in [like Donald] Trump, I think that equity prices start to back off drastically," RJO Futures strategist and trader Phillip Streible said Thursday on CNBC's "Trading Nation." "Remember, his policy is to punish those companies that operate outside the U.S. with taxation and other controls. So I think that equities would start to push back down."
Trump solidified his grasp on the Republican nomination this week, when competitors Ted Cruz and John Kasich suspending their campaigns. His proposed restrictive trade policies have led some to say his election could lead to deleterious effects for stocks. In a March interview on CNBC's "Fast Money," Wedbush director of equity sales trading Ian Winer said that if Trump wins and his policies are enacted, the S&P 500 could fall by 50 percent.
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Trump discussed his economic policies Thursday on CNBC's "Squawk Box." The presumptive Republican nominee maintained in a phone interview that he would renegotiate the country's trade agreements and argued that China is manipulating U.S. currency, giving the country an unfair economic advantage.
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Streible has envisioned a different outcome should a Democrat take the White House.
"If you do get that Democratic nominee and winner, I think that the equities go on another Obama-type move, and we see equities push up into uncharted territories," he said.
But Fort Pitt Capital portfolio manager Kim Forrest believes the S&P will break out of its range not because of politics, but because of the Federal Reserve.
"I think it has to do everything with interest rates and just the underlying health of the economy," she said. "The multiple [of price as compared to earnings] is set by interest rates. The lower the interest rate, the higher the multiple and investors are willing to pay up for. The economy is getting better very, very slowly, but not enough to drive up revenues meaningfully and interest rates can't go much lower."
"This is probably the range we're in until either the interest rate changes, or the economy gets remarkably better," Forrest added.