Based on the aggregated intelligence of 115,000-plus investors participating in Motley Fool CAPS, the Fool's free investing community, oil and gas refiner Tesoro (NYSE:TSO) has earned a respected four-star ranking. While five-star stocks have been the best performers, our data has shown that four-star stocks still outshine the market by a significant margin and shouldn't be taken lightly; conversely, low-rated stocks have woefully lagged the market average.

With that in mind, let's take a closer look at Tesoro's business, and see what CAPS investors are saying about the stock right now.

Tesoro facts 

   

Headquarters (Founded)

San Antonio, Texas (1968)

Market Cap

$2.55 billion

Industry

Oil and Gas Refining and Marketing

TTM Revenue

$27.48 billion

Management

CEO Bruce Smith (since 1995)

CFO Otto Schwethelm (since 2007)

Return on Equity (average last three years)

23.4%

Major Competitors

ExxonMobil (NYSE:XOM)

Valero Energy (NYSE:VLO)

CAPS members bullish on TSO also bullish on

Transocean (NYSE:RIG)

General Electric (NYSE:GE)

CAPS members bearish on TSO also bearish on

Lehman Brothers (NYSE:LEH)

Ambac Financial (NYSE:ABK)

Sources: Capital IQ, a division of Standard & Poor's, and Motley Fool CAPS. TTM = trailing 12 months.

Over on CAPS, fully 288 of 304 of the CAPS All-Stars who have rated Tesoro -- some 94% -- believe the stock will outperform the S&P 500 going forward. These include VegetableFool and carguy12345, both of whom are ranked in the top 15% of our community.

Three weeks ago, VegetableFool pointed out, "Pure refining plays are dead cheap at P/E ratios of around 4-5. Thats with earnings in the dumper. Nothing but upside or bankruptcy; I figure upside."

An earlier pitch from carguy12345 in 2007 shares that bullish mind-set, stressing Tesoro's tasty long-term traits:

I'm a firm believer in the peak oil theory. Gotta go with T. Boone Pickens on this one. [Tesoro] is a big name for oil in California (where they have the most cars and use the most gasoline in the US) and Hawaii which has to import it's oil. Add to that increased demand for oil from Aias markets and this is a commodity that is going to be in scarce supply over the long term.

What do you think about Tesoro, or any other stock for that matter? Make your voice heard on Motley Fool CAPS today. More than 115,000 investors are waiting to hear what you have to say. CAPS is 100% free, so simply click here to get started.

Foolish contributor Brian Pacampara owns no position in any of the companies mentioned. The Fool's disclosure policy always gets a perfect score.