By Ellen Freilich NEW YORK, Nov 8 (Reuters) - Most U.S. Treasuries traded slightly higher on Thursday though bonds at the long end of the yield curve were weaker before a sale of 30-year securities later in the day. As traders positioned for the U.S. Treasury's final refunding auction of the week, a $16 billion sale of 30-year bonds, the 30-year Treasury price was down 2/32 of a point, leaving the yield at 2.85 percent. The 30-year auction involves "ample uncertainties" especially in the months in which there are quarterly refundings, because the size of the auction is $3 billion larger than in monthly re-openings, said Cantor Fitzgerald analyst Justin Lederer in New York. "Overall we expect decent demand for the long end as investors need duration and yield and look for rates to stay low with (President Barack) Obama winning a second term," he said. A big supporting role for the 30-year Treasury auction is played by the Federal Reserve which is currently buying about 92 percent of new issuance in the long end in its "Operation Twist" monetary stimulus program, Lederer said. That program is due to end next month, but many market participants believe the Fed will announce more Treasury purchases at the December meeting of the Federal Open Market Committee, the Fed's monetary policy-making arm. "The 30-year, like every other sector of the curve, has been stuck in an extremely tight range since mid-September," Lederer noted, its yield moving between 2.77 percent and 3.02 percent. "We do not expect this range to break significantly in the near term," he said. With the long end of the curve undeperforming, prices of Treasury instruments in the "belly", or middle, of the yield curve were narrowly higher, enjoying a mild safe-haven bid based on uncertainty about the euro zone and U.S. fiscal concerns. Obama's decisive election victory supported bonds amid expectations for modest economic growth and accommodative, bond-friendly monetary policy, but financial markets are wondering whether the White House and Congress will be able to avoid or minimize the potential damage of a $600 billion package of automatic tax increases and spending cuts, due to take effect at the end of this year. "A Democratic president and Republican House will need to come together to deal with the nation's fiscal health," said Zach Pandl, strategist at Columbia Management in Minneapolis. "Having the election over is a relief, but investors still need to see a favorable resolution of the fiscal cliff before taking a more optimistic view on the U.S. economy," he said. The uncertainty over the "fiscal cliff" issue continued to lend a little safe-haven support to U.S. Treasuries. So did concern about the European debt crisis. Greek lawmakers - by a very thin margin - approved an austerity package constructed to get international aid. The coalition government still needs to pass the 2013 budget in a vote expected on Sunday. Spain showed investors will buy its long-term debt on Thursday with a successful bond auction that completed its 2012 issuance program. The European Central Bank kept rates on hold and its president, Mario Draghi, sounded downbeat on the euro zone economy and said he was ready to start new purchases of bonds. News the U.S. trade deficit narrowed in September due to a rise in U.S. exports had little influence on bonds. The impact of a drop in new jobless claims to 355,000 was also slight.