Aaron Task celebrated the start of the second half by predicting which first-half losers will turn into winners by the end of the year. Task, co-executive editor of TheStreet.com, subbed Friday for the vacationing Jim Cramer on his "Real Money" radio show. Using a list supplied by The Wall Street Journal, Task reviewed the mega-cap stocks that had the roughest first half and -- contrarian that he is -- forecast a turnaround for most of them. Wal-Mart ( WMT) has had a terrible first half, but Task said that negative sentiment has reached a peak. Should the economy slow down in the second half, shoppers may opt to walk the aisles in their local Wal-Mart as opposed to a more upscale and pricey store, Task says. With regard to drugmaker Merck ( MRK), Task says institutions have to own it and will like it even more at these depressed levels, especially with its current juicy 4.59% dividend yield. Another first-half loser likely to turn around with a slowing economy is McDonald's ( MCD) Task says. Same goes for IBM ( IBM), another American icon of a company, which Task says is being hit by too much negative sentiment. Aluminum giant Alcoa ( AA) kicks off earnings season next week, and Task says the company could pop if it provides better-than-expected earnings, mostly because it has been out of favor for so long. And as for 3M ( MMM), which fell over a management shuffle, Task says it may be time to dip a toe in and start buying. As for the first-half winners, Task advised listeners to take profits in Boeing ( BA) which is up 27% year-to-date. And despite Cramer's love for shares of Intel ( INTC) Task warned that there very well may be "too much optimism going into the quarterly report." Task's guest John Rutledge, chairman of Rutledge Capital, spoke more about inflation and exchange-traded funds than individual stocks.