-Stock futures decline as focus shifts from Greece elections to Spain--Europe pares gains on uncertainty about New Democracy's slim victory--Housing market index for June expected to decline slightlyBy Tomi KilgoreNEW YORK--U.S. stock futures fell Monday, erasing earlier gains, as initial relief over the pro-austerity party's narrow victory in Greece's elections gave way to increasing worries about Spain.Dow Jones Industrial Average futures declined 52 points, or 0.4%, to 12658, erasing earlier gains of as much as 92 points.Standard & Poor's 500-stock index futures lost 5 points, or 0.4%, to 1332 and Nasdaq 100 futures slipped 3 points, or 0.1%, to 2561. Changes in stock futures don't always accurately predict stock moves after the opening bell.On the economic calendar, the housing market index for June is due out at 10 a.m. EDT, with economists surveyed by Dow Jones Newswires expecting a decline to 28 from 29 in May.European markets were mostly up but well off earlier highs, as the New Democracy party's slim victory in Greece and Spain's brewing crisis sapped the initial excitement over the Greek elections. The Stoxx Europe 600 was up 0.2%, but was trading up 1% soon after the open.Although New Democracy's victory assures that Greece will stay in the euro for now, there was some worry about the party's ability to form a viable coalition.Separately, the yield on 10-year Spanish bonds rose above 7% and IBEX-35 stock index slumped 1.6%, as investors worried that Spain would soon need a bailout of its own, after the country's banking sector already received a bailout offer from European partners.Meanwhile, Asian markets were broadly higher following the Greece election results, with Japan's Nikkei Stock Average surging 1.8% and China's Shanghai Composite rising 0.4%.Crude oil futures fell 0.9% to $83.29 a barrel, while gold futures gave up 0.2% to $1624.40 an ounce. The U.S. dollar rose against the euro but lost some ground against the yen.In corporate news, shares of Facebook slipped 0.4% in premarket trading after the social networking giant said its chief technology officer, Bret Taylor, was leaving that company to work on another start up. The stock ran up 6.1% on Friday, the biggest one-day gain since the company went public on May 18.Extorre Gold Mines surged 56% after the gold miner said it agreed to be acquired by Yamana Gold in a cash-and-stock deal valued at roughly $400 million.Infinity Pharmaceuticals dropped 23% after the company said it stopped a Phase 2 trial of its treatment for bone and cartilage cancers, citing disappointing clinical data.