(At 5:10 p.m. EDT) The Dow Jones Industrial Average notched a sixth-straight winning session, led by a jump in Caterpillar ( CAT) and a handful of other components set to report earnings Tuesday. The blue chip average once again finished at the highs of the session, up 104.21 points to 8848.15, putting the index in positive territory for the year. Perhaps more impressive, Monday's close is the highest for the Dow since Jan. 6, when it finished at 9015. As I mentioned before, the Dow's biggest contribution came from Caterpillar, as the company was upgraded to buy by Bank of America-Merrill Lynch, even though the company claimed second-quarter results from the construction-equipment maker should be weak. The stock ended with a gain of $2.66, or 7.8%. With Caterpillar set to report earnings early Tuesday, it will be curious to see if this is another case of buy the rumor, sell the news. When it last reported quarterly results, Caterpillar slashed its guidance for 2009 to $1.25 a share. Currently, the Thomson Reuters average estimate sits at $1.03 a share, indicating Caterpillar may have more cutting to do. With such a big jump Monday, the Dow's direction Tuesday may now depend on whether investors will be able to brush away any disappointing news from Caterpillar as easily as BofA-Merrill apparently can. Luckily for bulls, even if Caterpillar's news is bad, there will be plenty of other Dow members for investors to focus on. Coca-Cola ( KO), DuPont ( DD), Merck ( MRK) and United Technologies ( UTX) all will report before Tuesday's opening bell.