The American stock market extended July’s advance on $25 billion of share buybacks and speculation second-quarter earnings will surpass analysts’ estimates.

ConocoPhillips, the third-largest American oil producer, rose to a record and Johnson & Johnson, the world’s biggest maker of health-care products, climbed the most in almost two months after saying they will repurchase stock. Alcoa Inc., the second-largest aluminum maker, led the Dow Jones Industrial Average to within 27 points of a record ahead of yesterday’s earnings report.

Companies have announced plans to buy $415 billion of their own equity this year, 24% more than in the same period in 2006, according to data compiled by Birinyi Associates Inc. as of June 29. Nineteen straight quarters of profit growth above 10% have left Standard & Poor’s 500 Index companies flush with cash.

“Buybacks have been the fuel for the stock market so far and will continue to be so,” the chief market strategist at Kanaly Trust Co. in Houston, Tim Hartzell, said.

The S&P 500 rose 1.41, or 0.1%, to 1531.85, its fifth straight day of advances. The Dow average increased 38.29, or 0.3%, to 13,649.97. The Nasdaq Composite Index added 3.51, or 0.1%, to 2670.02.

Declines in bond yields and oil prices as well as acquisitions and takeover speculation also boosted stocks. Google Inc. advanced after buying closely held Postini Inc. and FedEx Corp. gained on a report that it may be ripe for a takeover bid.

ConocoPhillips jumped $3.01 to $84.05. The company said its buyback plan of as much as $15 billion is approved through the end of 2008. The stock led a gauge of energy companies in the S&P 500 to the steepest gain among 10 industries.

Johnson & Johnson added 59 cents to $62.72. The company, facing competition to its bestselling drug Risperdal, will use a combination of cash and debt to fund a $10 billion buyback meant to bolster the stock price until the company can bring new products to the market.

Alcoa advanced 70 cents, or 1.7%, to $42.36 for the top gain in the Dow average. The company reported after markets closed that profit, excluding some items, was 81 cents a share, a penny higher than the average estimate in a Bloomberg survey. The shares slipped 50 cents to $41.86 in extended trading.

Alcoa is pursuing a $27.7 billion hostile bid for rival Alcan Inc. that would allow it to double output. Alcoa’s shares climbed to a sixyear high in June after the Times of London said BHP Billiton Ltd., the world’s largest mining company, was reviving plans for a $40 billion offer for Alcoa.

Analysts estimate S&P 500 members posted average profit growthof 4.8% in the second quarter, according to data compiled by Bloomberg. Their earnings grew 10.3% in the January-to-March period, more than triple analysts’ forecasts of 3.1% on April 13.

“Investors will be keenly interested in second-quarter earnings,” a senior investment officer at AIM Advisors Inc. in Houston, FritzMeyer, said. “There are some positive surprises in store. That should bode well for the market.”

Intel Corp. added 28 cents to $24.96. UBS AG raised its price estimate for the shares to $30 from $27. Intel is poised to “drive faster growth and higher margins” with stable pricing and consolidating market share, wrote UBS analysts including Uche Orji. JPMorgan increased its second-quarter sales, earnings, and gross margin estimates for Intel, citing “healthy” demand for personal computers from emerging markets such as China. Boeing Co. climbed $1.02 to $99.90. The company Sunday unveiled its 787 Dreamliner at an event broadcast live by satellite in nine languages.

A gauge of financial shares in the S&P 500 dropped 0.3% and was the biggest drag on the index.

In other markets, the yield on the benchmark 10-year Treasury note fell 3 basis points, or 0.03 percentage points, to 5.15% on speculation that subprime mortgage losses and higher lending rates may slow economic growth.

Crude oil fell from a 10-month high, dropping 53 cents to $72.28 a barrel in New York, on expectations demand will decline because of the unexpected shutdown of units at American refineries.