By DAVID ESPO and JIM KUHNHENNWASHINGTON (AP) â¿¿ The end game at hand, the White House and Senate leaders made a final stab at compromise Friday night to prevent middle-class tax increases from taking effect at the turn of the new year and possibly block sweeping spending cuts as well. "I'm optimistic we may still be able to reach an agreement that can pass both houses in time," President Barack Obama said at the White House after meeting for more than an hour with top lawmakers from both houses. Surprisingly, after weeks of postelection gridlock, Senate leaders sounded even more bullish. The Republican leader, Sen. Mitch McConnell of Kentucky, said he was "hopeful and optimistic" of a deal that could be presented to rank-and-file lawmakers as early as Sunday, a little more than 24 hours before the year-end deadline. Said Majority Leader Harry Reid: "I'm going to do everything I can" to prevent the tax increases and spending cuts that threaten to send the economy into recession. He cautioned, "Whatever we come up with is going to be imperfect." House Speaker John Boehner, a Republican who has struggled recently with anti-tax rebels inside his own party, said through an aide he would await the results of the talks between the Senate and White House. Under a timetable sketched by congressional aides, any agreement would first go to the Senate for a vote. The House would then be asked to assent, possibly as late as Jan. 2, the final full day before a new Congress takes office. Officials said there was a general understanding that any agreement would block scheduled income tax increases for middle class earners while letting rates rise at upper income levels. Democrats said Obama was sticking to his campaign call for increases above $250,000 in annual income, even though in recent negotiations he said he could accept $400,000.