Updated: 12:16 a.m.

Senate Majority Leader Harry Reid got what he wanted from Tuesday’s elections. But it may be a case of “be careful what you wish for.”

The Nevada Democrat no doubt views the results as a major victory. His party did something that seemed unlikely two years ago, retaining the Senate majority and even picking up some GOP-held seats that seemed out of reach earlier this year. Plus, the Associated Press projects that President Barack Obama will still be working with him from just down the street.

Though the final makeup of the Senate is still uncertain, Democrats have already picked up at least three GOP-held seats, assuming Maine Independent Angus King caucuses with them as expected. The party’s ability to also hold on to Virginia’s Senate seat then put a GOP takeover out of reach.

But after a protracted campaign that was supposed to break the political deadlock in Washington, D.C., voters essentially reaffirmed the status quo — Obama and Senate Democrats lined up against Speaker John Boehner (R-Ohio) and his headstrong conservative majority in the House.

If party leaders were waiting for voters to give one side or the other a mandate to govern — and to resolve the tax and spending issues involved in negotiations to avoid the “fiscal cliff” — they will have to continue their battle for the upper hand.

For Reid, a major test will be whether he can generate change in the Senate that will produce legislative accomplishments for both his caucus and the president. The first question he will confront in the 113th Congress will be whether to bow to calls in his own party to restrict the rights of the minority.

After initially rejecting attempts to tighten filibuster rules, Reid earlier this year said he had been wrong and would support efforts next year to make it easier to move legislation through the chamber.

“I believe that if you look at what Lyndon Johnson had to do when he was the leader as I am, it was a different world. Why? You know how many filibusters he had to try to override? One. Me? Two hundred and forty-eight,” Reid said in a recent interview with CBS’ “60 Minutes.”

Indeed, Republican blockades of procedural votes — a tactic Reid used as Minority Leader — have become more prevalent. And in some of the Senate’s most frustrating moments this year, Reid effectively threw up his hands and conceded that some newer Democrats, including Sens. Jeff Merkley (Ore.) and Tom Udall (N.M.), who pushed for filibuster restrictions in 2006 were “right.”

“The early part of the next Congress could be defined by two issues, filibuster reform and all of the tax and spending issues,” said former Reid spokesman Jim Manley.

Sources tracking discussion of changing the filibuster say Reid has been talking about changes such as eliminating filibusters on motions to proceed and requiring Senators staging filibusters to hold the floor in person. A vote on such changes would likely occur in January or February.

Sources have speculated that to try to preserve the filibuster but enact some reforms, Reid may decide to push through a rule forcing any Senator who wants to filibuster to be on the floor to register objections.

Senate Majority Whip Dick Durbin (D-Ill.) on MSNBC on Tuesday night seemed to hint at that outcome.

“It depends on the numbers of Democratic Senators elected as to whether there will be filibuster reform,” Durbin said. “I’ve taken a look at some of the proposals, and I think we need them.”

He added that the Senate “needs to be functional, we need reform that makes a filibuster count. You want to filibuster? Stick around, don’t go out to dinner.”

Using a majority vote to push through a controversial Senate rules change could ignite a furious partisan backlash from Republicans that could stymie Obama’s agenda at the very time the president will want to capitalize on his re-election.

Manley said changing the filibuster rules would constrain Minority Leader Mitch McConnell (R-Ky.). But he cautioned that McConnell likely has already gamed out scenarios that would allow him to impede the Senate’s progress in other ways.

“I am confident that he has already figured out a way to do so,” Manley said. “The question is whether he will. … Something is going to have to give, because people are sick and tired of gridlock.”

Even if Reid decides to try to limit filibusters in the new Congress, he will not have any new tools to knock down GOP roadblocks during the post-election session beginning next week.

While both parties hoped the elections would bring some clarity to fiscal cliff deliberations, the scenario now appears to be the same players re-engaging on the same issues they have fought over throughout this Congress. The Bush administration tax cuts expire Jan. 1, at the same time that $1.2 trillion in automatic cuts in discretionary spending begin to take effect. Government borrowing is expected to hit the debt ceiling by year’s end, and the Treasury can only do so much to give Congress extra time to get its act together in the opening months of 2013.

Democrats have largely assumed that an Obama re-election — along with continued Democratic control of the Senate — would shake loose Republicans willing to capitulate on the president’s demand that taxes on the highest earners go up in the new year. GOP sources have said Obama’s victory may put some tax increases on the table for them, but not the top tax rates for the wealthy. Indeed, Boehner took the stage at the GOP election watch party in Washington early on Tuesday night to declare that raising taxes on the rich is a nonstarter in the lame duck.

But Reid struck a conciliatory tone Tuesday night when it became clear he would keep his job.

“Now that the election is over, it’s time to put politics aside, and work together to find solutions,” Reid said in a statement. “The strategy of obstruction, gridlock and delay was soundly rejected by the American people. Now, they are looking to us for solutions.”

And he subtly warned Republicans not to try to punt decisions on the fiscal cliff until the next Congress, saying: “This is no time for excuses. This is no time for putting things off until later. We can achieve big things when we work together. And the middle class is counting on us to achieve big things in the months ahead.”

Because bridging the divide between the president and the Speaker appears to be the most difficult task, Reid may have to work to prevent himself from being sidelined in what is likely to be a negotiation between Boehner and Obama.

Toward the end of the debt limit negotiations in the summer of 2011, Reid was largely shut out by Obama and Boehner, who spent weeks trying to hash out a “grand bargain” that would have included changes in entitlement programs and revenue increases. In the end, Obama, Boehner and McConnell came together to find an agreement to avert default.

Because Democrats and Republicans saw little reason to begin negotiating in any meaningful way on the fiscal cliff before the elections, Congress now has only a few weeks to find at least a temporary solution.

Bipartisan consensus has begun to coalesce around overhauling the tax code and eliminating some tax breaks, especially for the wealthiest. Republicans would like to see any revenue gained used to keep tax rates low.

Reid, who emerged as a top Democratic attack dog in the 2012 cycle, loves to chide Republicans about their relationship to Grover Norquist, the Americans for Tax Reform president whom Reid calls “the most powerful man in Washington.”

Democrats, however, are divided on where the revenue from tax changes should go. Those working in bipartisan budget groups, such as the Senate’s “gangs,” always have been open to using some of that revenue to keep tax rates low while using some to reduce the deficit. But some Senate Democrats, including Conference Vice Chairman Charles Schumer (N.Y.), favor using new revenue to pay down the national debt.

Reid will have to navigate the divisions within his own ranks as he determines what approach to take in negotiating with the Republicans, who have not been easy talking partners on these issues.

Regardless of where they stand on the details, Democrats — from Schumer to Finance Chairman Max Baucus to former supercommittee Chairwoman Patty Murray — have during the past few months intimated that their party would prefer to let the tax increases and spending cuts happen rather than extend expensive tax breaks to the wealthiest 2 percent of Americans.

“There is absolutely no reason — not one — that we need to extend the tax cuts for the rich as a precondition for reforming the tax code,” Murray said in a July address at the Brookings Institution. “Republicans are going to have to accept that tax reform isn’t going to be a back door way for them sneak through more tax cuts for the rich. And it is going to have to raise revenue to help rein in the deficit and debt.”

Reid will be taking many of his cues from his fellow Democrat in the White House. On the campaign trail, Obama emphasized completing comprehensive immigration legislation and passing a jobs plan he introduced in the fall of 2011. But the lack of bipartisan partners, and the absence of negotiating stalwarts such as the late Sen. Edward Kennedy (D-Mass.), who was the lead sponsor of a failed effort on immigration early in Obama’s first term, could pose a challenge for Reid, who, more than committee chairmen, seemed to be at the center of all the major policy debates in this Congress.

It’s a full plate for Reid, but he asked for it.

Niels Lesniewski contributed to this report.