ROUGH CUT (NO REPORTER NARRATION)

STORY: Senate Majority Leader Harry Reid said that talks continue to avert the fiscal cliff -- but differences remain between Democrats and Republicans.

Taxes are on track to rise for many Americans this week unless lawmakers could cut a last-minute deal on Monday to avoid the "fiscal cliff," an outcome that seemed unlikely, but still possible.

Financial markets were on edge only hours before the midnight arrival at the long-awaited "cliff," an assortment of $600 billion in tax hikes and broad federal spending cuts on defense and domestic programs that has defied a political solution.

Senate Republican Leader Mitch McConnell and Democratic Vice President Joe Biden carried on "good talks" late into Sunday evening, aides said. Details of their discussions were unclear.

Any resolution in the tug-of-war over taxes and spending cuts forged in the Senate would need to win approval in the House of Representatives and the outcome in that chamber was uncertain.