Tech bellwether IBM ( IBM) could pull off yet another upside surprise when it reports earnings after the bell Thursday. At least that's the line taken by some of the more bullish houses on Wall Street, following Big Blue's January comments that 2004 will mark the beginning of an upturn in tech spending.

The current consensus estimate assumes earnings of 93 cents on sales of $21.914 billion, according to Thomson First Call.

Prudential Equity Group predicts IBM's first-quarter sales could show upside of as much as $300 million or $400 million, and earnings could exceed consensus by 2 cents to 3 cents. Merrill Lynch and Goldman Sachs are less ebullient, but agree slight upside is possible.

As is often the case, most buy-side participants aren't as bullish as their sell-side counterparts. Many investors reserve their bullishness for a few quarters down the road, downplaying the weight of the upcoming report by noting IBM isn't likely to see real leverage until enterprise spending rises in earnest. And there's little evidence that has happened yet.

"I don't have really high expectations in terms of what we're seeing Thursday ," said Duane Roberts, a portfolio manager for Dana Investment Advisors, which holds IBM. "The impression I'm getting is that spending isn't picking up quickly. I think it will probably be the second half of the year, if not, 2005."

At that point, IBM should be in a sweet spot. "I think the completeness of their package makes them a little unique," said Roberts. "I like their valuation level and the general direction with the services business and with Linux. As information technology spending picks up, with their services and with their hardware as strong as it's been, I think IBM will benefit."

Fans of the stock point out that not only is IBM's business expected to gain momentum over the course of this year, but also its massive hardware arm is currently gaining at the expense of its competitors.

Still, the shares have lagged the market year to date as investors demand more evidence of the long-awaited (and still mostly elusive) upturn in enterprise spending.