The U.S. stock market's rally to five-year highs is not a "sugar-high" courtesy of the Federal Reserve, but a result of a strengthening American economy, market watchers told CNBC on Monday, after the S&P 500 index closed Friday at its highest level since Dec. 31, 2007.
"This [rally] is a fundamentally driven advance in the stock market by growth in the economy," said Wells Capital Management's James Paulsen on CNBC's "Squawk Box."
Richard Bernstein, CEO of Richard Bernstein Advisors, agreed. "The economy is not strong in the absolute sense, but it continues to improve and that's why the stock market is up." He added, "There's very little to say that's going to change."
Despite Friday's surge, the S&P 500 is still about 6 percent away from its all-time closing high on Oct. 9, 2007. The Dow Industrial Average is about 5 percent from its record close on that same day.
There are a number of forces that could propel stocks to those new highs, or stop the rally in its tracks, such as the political battles over the U.S. debt ceiling and other budget matters.
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But Wells Capital Chief Investment Strategist Paulsen told CNBC that Washington's squabbles will have less of a market impact going forward.
"We've been desensitizing to some of these Armageddon stories," Paulsen observed. "The markets will react less to this debt ceiling than they did to the fiscal cliff."
While he thinks that the current rally in the markets isn't solely Fed-driven, Paulsen does believe monetary policy will be the main focus later this year.
"Fed policy is going to take over the investment consciousness by the end of this year," he said. "Fiscal issues are going to fade away, and it's all going to be about monetary issues."
Meanwhile, Bernstein of Bernstein Advisors told CNBC that even if the economy continues to improve and the Fed starts to tighten down the road, the stock rally could still have some legs.
"In every cycle there's a point when the Fed starts to tighten. That's not generally the end of the bull market," he argued. "The end of the bull market is when the Fed tightens too much. And we're years away from that right now."
—By CNBC's Matthew J. Belvedere; Follow him on Twitter