The index on Monday scored its third straight record—closing at 2,129 and bringing year-to-date gains to 3.4 percent.
Lee predicts 2,325 for the S&P by the end of 2015. "In some ways, that's a catch-up because Europe has done great this year," he said. "Japan has done great."
As of Monday's close, the Dow was up nearly 2.7 percent for 2015, while the Nasdaq was up 7.2 percent.
"The U.S. consumer is still one of the most important engines for growth," Lee said on CNBC's "Squawk Box."
"They're showing signs of employment life, not necessarily spending life yet," he added. "But once that turns, especially we're seeing that in housing, I think the focus comes back to the U.S., and there's a nice earnings story."
In the latest earnings season, in which expectations were dim, many domestic companies posted high single-digit growth, he said, noting they benefited from lower oil prices.
On the economic front, "good news is good news because everybody is expecting bad news," Lee said. "I'd say this is still the least-loved six-year rally in history."
"The market is usually good at predicting changes in [economic] trend," he continued. "I think the market is telling us the cadence in the next couple of quarters is going to be quite good."
Another question mark for investors has been the dire debt situation in Greece. Government officials there insisted Tuesday a deal was imminent with international lenders over reforms as a condition for more bailout money.
"The good news is the markets don't think there's a systemic risk" from Greece, Lee said. The problems facing Athens have been "well telegraphed."
Lee launched his own boutique equity research firm, Fundstrat Global Advisors last year, after leaving JPMorgan Chase as chief equity strategist.