* Wal-Mart shares lead Dow after quarterly report
* Popeyes shares soar after $1.8 bln buyout agreement
* All S&P 500 sectors in positive territory
* Indexes up: Dow 0.47 pct, S&P 0.43 pct, Nasdaq 0.27 pct (Updates to late afternoon)
By Lewis Krauskopf
Feb 21 (Reuters) - U.S. stocks rose to fresh record highs on Tuesday, boosted by strong earnings reports from Wal-Mart and other retailers and continued optimism about the economic agenda of President Donald Trump.
Wal-Mart's shares were the top stock in the Dow Jones Industrial Average, rising 3.3 percent after the world's largest retailer reported higher-than-expected U.S. sales.
More than one in every six stocks on the S&P 500 hit a new 52-week high as a post-election rally extended. The benchmark index has climbed more than 10 percent since Trump's Nov. 8 election, sparked by the promise of tax reforms, reduced regulations and increased infrastructure spending.
"There was a period last week, I think, where people were getting a little worried about whether the administration was getting sidetracked," said Rick Meckler, president of LibertyView Capital Management in Jersey City, New Jersey.
"A couple days later, those worries seem to have temporarily subsided," Meckler said. "If their platform can go through, I think a lot of investors see it as very positive for stock valuations."
The Dow Jones Industrial Average rose 96.03 points, or 0.47 percent, to 20,720.08, the S&P 500 gained 10.19 points, or 0.43 percent, to 2,361.35 and the Nasdaq Composite added 15.79 points, or 0.27 percent, to 5,854.37.
All three indexes tallied intraday all-time highs.
The S&P is trading at 17.8 times earnings estimates for the next 12 months, above the long-term average of 15 times, according to Thomson Reuters Datastream.
"There is no doubt in anyone's mind that the market has become over-extended and is due for a pullback," said Quincy Krosby, market strategist at Prudential Financial in Newark, New Jersey.
"That said, when you have this kind of momentum, it is very hard to sit on the sidelines."
Aside from Wal-Mart, shares of department store operator Macy's and home improvement chain Home Depot rose modestly after their quarterly reports.
Overall profit for S&P 500 companies is estimated to have risen 7.5 percent in the fourth quarter, Thomson Reuters I/B/E/S said in a report last Friday.
All 11 major S&P sectors were higher on Tuesday.
In other corporate news, Popeyes Louisiana Kitchen jumped 19 percent after Burger King owner Restaurant Brands agreed to acquire the restaurant chain for $1.8 billion.
Advancing issues outnumbered declining ones on the NYSE by a 1.99-to-1 ratio; on Nasdaq, a 1.12-to-1 ratio favored advancers.
The S&P 500 posted 88 new 52-week highs and no new lows; the Nasdaq Composite recorded 204 new highs and 24 new lows. (Additional reporting by Yashaswini Swamynathan in Bengaluru; Editing by Saumyadeb Chakrabarty and Nick Zieminski)