Futures for the Dow Jones Industrial Average gained 14 points to 13,585, while those for the S&P 500 gained 1.4 points to 1,529.
Nasdaq 100 futures rose 3.5 points to 1,919.
Investors also cheered crude oil falling back below $66 a barrel. On Monday, crude futures had rallied as violence in Nigeria, Lebanon and Israel, along with concerns over supply led oil to a three-session win of 6%.
"The focus on M & A activity and global growth outweighed the rally in crude," said Marc Pado, market strategist at Cantor Fitzgerald.
On Tuesday, MGM Mirage jumped 24% before the open. Billionaire Kirk Kerkorian's firm Tracinda Corp. said it's in talks to buy two of MGM's best-know Las Vegas landmarks, the Bellagio and CityCenter.
Fremont General said it's proposing to sell its commercial real estate lending business and outstanding loan portfolio to iStar Financial for $1.9 billion.
Whole Foods Markets extended its tender offer for Wild Oats Markets to June 20 from May 22. Whole Foods agreed to buy Wild Oats for roughly $565 million. It noted that members of the Federal Trade Commission staff voiced concerns about perceived anticompetitive effects. The FTC hasn't decided whether to challenge the deal.
Harbinger offered to buy 40.8 million shares it doesn't already own in OpenWave Systems for $8.30 a share. The fund manager plans to recommend replacing the company's management and board and then buying BridgePort.
China takes center stage
With no key economic reports Tuesday, markets will be paying close attention to talks between U.S. Treasury Secretary Henry Paulson and Chinese government officials. China last week widened the daily trading band for the yuan against the dollar in what many saw as a symbolic gesture.
The Chinese government also in an unprecedented move said it would put $3 billion of its massive foreign exchange holdings to work by investing in The Blackstone Group, a leveraged buyout firm preparing an initial public offering.
The dollar was nearly flat against key rivals. Gold fell slightly, along with crude oil, and Treasury bonds fell back, sending yields higher.
After the closing bell, Computer Sciences , Medtronic and Analog Devices are due to report results.
Pacific Sunwear , the teen-apparel retailer, said first-quarter sales surpassed expectations.
Dynegy dropped 4.7% after Chevron said it would sell 96.9 million Class A shares in an underwritten offering.
Staples reported a 12% profit rise on 8% sales growth in the first quarter, helped by sales of laptop computers.
Tech Data reported a 23% profit decline but 9% sales growth, while Autozone reported a 5% profit rise on 4% sales growth.
By Nick Godt