U.S. stocks rallied on Monday, with the S&P 500 crossing 2,000 for the first time, lifted by a round of corporate deals and optimism that the European Central Bank would embark on further moves to stimulate the European economy.
"I've got the bottle ready to open," said Howard Silverblatt, senior index analyst at S&P Dow Jones Indices, referring to a 1998 Dom Perignon champagne that he plans to pop when the S&P 500 finishes above the milestone.
"Closing above 2,000 would be a bit more significant because then you can bounce from there; it gives people a sense of confidence more than anything else; it's a psychological mark, not a technical mark," said JJ Kinahan, chief strategist at TD Ameritrade.
"It's important that we made it; it's a milestone, but more importantly is it's a good time to review where you've been and where you're going; that's the true take away for the individual, as institutions should be doing it anyway," said Silverblatt.
Remarks Friday by ECB President Mario Draghi at the Jackson Hole, Wyoming, meeting of central bankers heightened expectations of additional policy easing.
Monday's gains are largely due to "Mr. Draghi's comments, his assurances that the European Union is as dedicated to keeping their markets as healthy as we are, it gave the market an excuse to test that 2,000 level," said Kinahan.
Burger King Worldwide is in talks to combine with Tim Hortons and moves its headquarters to Canada. Switzerland's Roche Holding has agreed to acquire U.S. biotechnology company InterMune for $8.3 billion in cash.
After a 123-point jump, the Dow Jones Industrial Average rose 75.65 points, or 0.4 percent, to 17,076.87, with JPMorgan Chase and Goldman Sachs Group leading blue-chip gains that extended to 24 of 30 components.
Furthering its climb into uncharted terrain and topping the 2,000 mark, the advanced 9.52 points, or 0.5 percent, to 1,997.92, with financials pacing sector gains.
The Nasdaq gained 18.80 points, or 0.4 percent, to 4,557.35.
The CBOE Volatility Index, a gauge of investor uncertainty, turned higher, up 2 percent to 11.7.
"The VIX is telling us the market has discounted geopolitical-type risks; the Russian-Ukraine situation hasn't gone away, but as long as it remains the status quo, the market will continue to discount it," Kinahan said.
For every two share falling, more than three rose on the New York Stock Exchange, where nearly 494 million shares traded. Composite volume surpassed 2.2 billion.
Dollar-denominated commodities including gold and oil declined, with gold futures for December delivery falling $1.30 to $1,278.90 an ounce and crude futures for October down 30 cents to $93.35 a barrel.
Monday's economic reports included data from the Commerce Department, which showed sales of new single-family homes fallingfor a second consecutive month in July.
"Housing is the area where we've seen the most split personality, we get three to four numbers, and they all show something different. But one number does not a trend make," said Kinahan.
A survey from financial-data firm Markit had the pace of growth in the nation's services sector declining for a second month in August, while a gauge of U.S. economic activity from the Chicago Federal Reserve illustrating expansion above historical trends.
On Friday, stocks mostly fell, with the S&P 500 halting a four-session win streak that lifted it to a record, as investors weighed rising tension between Russia and Ukraine and speeches by the ECB's Draghi and Federal Reserve Chair Janet Yellen.
—By CNBC's Kate Gibson
Coming Up This Week:
8:30 a.m.: Durable goods
9:00 a.m.: S&P/Case-Shiller home prices
9:00 a.m.: FHFA home prices
10:00 a.m.: Consumer confidence
10:00 am Richmond Fed survey
1:00 p.m.: $29 billion 2-year auction
Earnings: Brown Forman, Chico's, Tiffany, Williams-Sonoma
1:00 p.m.: $35 billion 5-year auction
8:30 a.m.: Initial claims
8:30 a.m.: Q2 GDP (second reading)
10:00 a.m.: Pending home sales
11:00 a.m.: Kansas City Fed survey
1:00 p.m.: $29 7-year note auction
8:30 a.m.: Personal income/spending
9:45 a.m.: Chicago PMI
9:55 a.m.: Consumer sentiment
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