Stock index futures were higher on Tuesday, extending gains from the previous session, as investors awaited a final reading on third-quarter economic growth and existing home sales data.

Existing home sales are expected to post their third straight monthly increase in November, a sign that the troubled housing market could be stabilizing. Gross domestic product is seen up 2.8 percent, according to a Reuters survey of economists.

There's a sense that GDP could be higher than consensus, and that's helping futures, said Kim Caughey, senior equity research analyst at Fort Pill Capital Group in Pittsburgh.

GDP will be the go-to number to get reassurance that the recession is truly over, while strong home sales will be another sign that indicators are going the right way.

The Richmond Fed survey for December is also on tap, and Micron Technology Inc , Cintas Corp and Red Hat Inc are all set to report quarterly results.

S&P 500 futures rose 5.9 points and were above fair value, a formula that evaluates pricing by taking into account interest rates, dividends and time to expiration on the contract. Dow Jones industrial average futures gained 47 points, and Nasdaq 100 futures added 10.75 points.

Ford Motor Co late Monday said it was offering buyouts and early retirement to all of its 41,000 U.S. factory workers, but did not provide a target number for how many would take the offers.

February crude futures slid 0.7 percent to $73.22 per barrel after OPEC agreed to leave its production targets unchanged, and ahead of the release of U.S. inventory data, which is expected to show a fall in stockpiles. The U.S. dollar index <.DXY> was little changed.

The proposed merger Live Nation Inc and Ticketmaster Inc was given a boost after a British regulatory body dropped objections and approved the deal.

Overseas, Japan's Nikkei average <.N225> rose 1.9 percent to reach a three-month closing high as a weaker yen lifted exporters. European stocks were broadly higher in Tuesday morning trading, led by oil and banks shares.

U.S. stocks rallied in Monday's session, with the Nasdaq hitting a 15-month high after brokerages upgraded two Dow components on improved profit prospects. Healthcare stocks advanced after a bill to overhaul the U.S. healthcare system passed a crucial test in the U.S. Senate. The measure is perceived as less damaging to industry profits than expected.

(Editing by Jeffrey Benkoe)