By Carla Mozee, MarketWatch

Ace to buy Chubb in $28 billion deal

U.S. stock futures jumped Wednesday, following a report that Greece's prime minister is prepared to agree to most bailout terms set by the debt-burdened country's creditors.

At the same time, Chubb Corp. rallied in premarket trade as the property & casualty insurer agreed to be bought by Ace Ltd.

Futures for the Dow Jones Industrial Average leapt 144 points, or 0.8%, to 17,667.00, and those for the S&P 500 rallied 14.60 points, or 0.7%, to 2,069.00. Nasdaq 100 futures picked up 34.50 points, or 0.8%, to 4,424.75.

Futures were propelled higher after the Financial Times reported Greek Prime Minister Alexis Tsipras is ready to accept nearly all of the conditions (http://www.marketwatch.com/story/greek-pm-tsipras-ready-to-accept-bailout-terms-ft-2015-07-01) to a new bailout deal that its international lenders proposed over the weekend. Tsipras due to address his nation later Wednesday. Follow the latest news in the Greek debt crisis (http://www.marketwatch.com/story/greek-debt-crisis-latest-news-on-wednesday-2015-07-01).

With that news, Wall Street will get trading in the second half of 2015 underway after a losing quarter for the S&P 500 Index . Data on tap Wednesday include a report on private-sector hiring, which could give a clue to the closely watched U.S. jobs report on Thursday.

Stocks globally had been hit this week as Greece and its creditors failed to work out a deal allowing the country access to new bailout funds. The S&P 500 has felt the weight of turmoil in Greece; it finished the second quarter lower by 0.2%, snapping a nine-quarter winning streak (http://www.marketwatch.com/story/us-stocks-eye-higher-open-after-greek-led-selloff-2015-06-30). In Tuesday's trade, the Dow Jones Industrial Average and the Nasdaq Composite ended slightly higher.

"With all the Greek furor, it's hard to believe that a month has passed and nonfarm payrolls will be released tomorrow," Brenda Kelly, head analyst at London Capital Group, wrote Wednesday.

Before the U.S. jobs reports is released Thursday -- a day earlier than usual because of the Independence Day holiday -- data on private-sector hiring in June will arrive from ADP at 8:15 a.m. Eastern Time.

A reading of 218,000 jobs would be "marginally better" than May's reading of 201,000, said Kelly. "Any better number here could ramp up the monetary tightening speculation," she said.

At the half-year mark, the S&P is 0.2% higher, while the Dow is 1.1% lower. The Nasdaq is up 5.3% so far this year. Read Need To Know: Humdrum first half bodes well for the rest of the year (http://www.marketwatch.com/story/a-humdrum-first-half-for-stocks-bodes-well-for-the-rest-of-the-year-2015-07-01).

Data: After the ADP report, investors will get Markit's reading of June manufacturing activity at 9:45 a.m. Eastern. Data on services activity for June will arrive from the Institute for Supply Management and construction-spending figures for May are both due at 10 a.m. Eastern. Figures on motor-vehicle sales for June should arrive throughout the day.

Corporates: Chubb (CB) shot up 34% ahead of the open after Ace (ACE) said it plans to buy the fellow insurer in cash and stock deal valued at $28.3 billion (http://www.marketwatch.com/story/ace-agrees-to-buy-rival-insurer-chubb-for-283-billion-2015-07-01-71034524). Ace shares climbed 10% premarket. The deal is expected to immediately boost Ace's per-share earnings and book value, and to generate $650 million savings.

Food supplier General Mills Inc. (GIS) posted weaker-than-expected revenue (http://www.marketwatch.com/story/general-millss-revenue-growth-lags-estimates-2015-07-01) in the fiscal fourth quarter while earnings excluding one-time items were above Wall Street expectations. Shares were up 0.5% in thin premarket trade.

Constellation Brands Inc. (STZ) shares gained 1.7% after the alcoholic-beverage maker said first-quarter sales rose 7% to $1.63 billion, above the FactSet estimate of $1.62 billion. The company also said it will buy the Meiomi wine brand for about $315 million.

Shares of Ford Motor Co. (F) and General Motors Co. (GM) will likely to move following the release of monthly car-sales data.

Nike Inc. (NKE) could see active trade after its co-founder Phil Knight created Swoosh LLC, a limited liability company, to hold his 128.5 million shares of Nike stock, equivalent to a 15% stake in the sports apparel company.

Other markets: European stocks surged on Wednesday's developments out of Greece. Asian markets overnight finished mixed. Stocks in Shanghai sank 5.2%, but Japan's Nikkei picked up 0.5%. Oil futures fell more than 1% while gold prices edged slightly higher. The dollar was up against most of its rivals on the ICE Dollar Index .

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