It's the Rodney Dangerfield of bull markets, LPL Financial Chief Market Strategist Jeff Kleintop said Tuesday.
"It gets no respect. This has been the most powerful bull market since World War II," he said. "We've only seen five, six other bull markets that have lasted this long, four years, five months. This is the best of all of them."
On CNBC's "Fast Money," Kleintop likened the stock market rally to a zombie.
"It's unkillable," he said. "I've taken to call it the 'Walking Dead' market, not only because it's unkillable, but it gets no respect."
While inflows into the stock market have been present, Kleintop argued that only about $10 billion has gone into equity mutual funds this year from individual investors.
(Read more: Stock tips from Wall Street's favorite small firm)
"I'm not saying they're still selling as they were in prior years," he said. "They're just not as bullish as I think they probably should be given how much they've been underinvested in recent years." he added.
Why should anyone care, asked Josh Brown of Fusion Analytics.
Kleintop said that underinvestment doesn't necessarily affect prices, "although certainly it would be nice to see the wind to the back of the markets of more buying. But I'm concerned individual investors haven't prepared for their retirement."
(Read more: Stock market set to 'rip higher,' Joe Terranova says)
Kleintop said that stocks still appeared buyable at current levels.
"This is a good opportunity," he said. "Looking ahead at the bond market vs. the stock market, this is the time I think individual investors should really consider reallocating back toward equities. I think it will extend but not simply because of the flow of money from the sidelines."
(Read more: 3 stocks that are better than IBM: Pro)
Kleintop noted that in the second quarter of 2013, there had been roughly $257 billion in buybacks, with about $80 billion in new issuance and IPOs combined.
"As I look to Q3, I think that will be true again, buybacks overwhelming the amount of new issuance and IPOs," he said. "And that may be true for the remainder of the year and into next year. PKW, the ticker, the ETF that tracks the buybacks index, the big winner this year. I think it will continue to be."
(Read more: Best ideas for market's bumpy ride ahead: Pro)
Kleintop said that his favorite stock market sector was consumer discretionary.
"The U.S. consumer is in a much better position than, I think, businesses are right now to further expand their spending. Credit is being further extended. Loan demand is picking up," he said. "I think the consumer is the place to be here in the second half.
Trader disclosure: On Aug. 6, 2013, the following stocks and commodities mentioned or intended to be mentioned on CNBC's "Fast Money" were owned by the "Fast Money" traders: Jon Najarian is long AAPL; Jon Najarian is long EBAY; Jon Najarian is long MGM; Jon Najarian is long TMO; Jon Najarian is long UNH; Jon Najarian is long WLL; Jon Najarian is long PPO; Jon Najarian is long SKUL; Simon Baker is long AAPL ; Simon Baker is long MS; Simon Baker is long GOOG; Simon Baker is long AMZN; Simon Baker is long NFLX; Simon Baker is long KORS; Simon Baker is long SNE; Josh Brown is long AAPL; Josh Brown is long KORS; Michael Murphy is long BAC; Michael Murphy is long C; Michael Murphy is long ADM; Kimberly Greenberg is long AAPL; Kimberly Greenberg is long KORS.