Dow gains 308 points

That's coupled with a 166-point gain on New Year's Eve - both fueled by the last-minute budget compromise. The Dow closed at 13,412, up 2.3 percent for the first session of 2013 - and the biggest one-day jump in four months. All the indexes were way up. The question is whether investors stay positive over the coming weeks as Congress and the White House grapple with other budget-related disputes. Especially worrisome would be another fight over raising the debt ceiling. From the WSJ:

Moody's Investors Service said in a statement Wednesday afternoon that the budget deal passed by Congress "does not...provide a meaningful improvement in the government's debt ratios over the medium term," reminding investors of the risks still hovering over markets. Moody's, which has put its top-notch rating of the U.S. government on a negative outlook, said the negotiations would likely affect its next ratings action. "It's good that they struck a deal, but there's a harder fight in the next six to eight weeks, and it's tough to imagine the market doesn't stay choppy until we get past the debt ceiling debate," said Richard England, portfolio manager for Atlanta Capital Management, which manages $14 billion in assets. "That doesn't mean the market has to go down in the interim, but maybe it doesn't go up much either."