With the Democrats now celebrating a Barack Obama presidency, as well as an increase in their majority control of Congress, the attention now turns to the hard part: legislating.
Democrats gained at least five Senate seats with three races still undecided, securing their grip on the chamber, but falling short of the supermajority needed to block GOP filibusters.
In the House, Democrats secured at least 18 new seats, but could pick up as many as 20 depending on the outcome of still undecided races.
Some say the increased majorities, coupled with Obama's White House win, will give the Democrats the ability to sweep party-friendly legislation through Congress, and without the threat of a veto. But political experts aren't so sure about the power of one-party rule.
"United government simply has not been a recipe of doing anything you want in Washington," said Princeton University political historian Julian Zelizer.
"Obviously, for the party in power, having a united government is better than having it divided," Zelizer said. "They have the room to maneuver and set the agenda and generally a better chance of passing legislation."
Before Election Day, the Democrats held majorities of 51-49 in the Senate and 235-199 in the House. Public confidence in one-party rule has ebbed and flowed over the last three decades, and holding the White House and both houses of Congress doesn't always make things easier.
Anne Mathias, the director of policy research at the Stanford Group in Washington, D.C., said one-party rule often only leads to division within the majority party.
"The Senate fights with the House as much as Republicans fight with Democrats," Mathias said. "The Democrats in the Senate are not a unified block and neither are the Democrats in the House."
Blue Dog Democrats, said Mathias, who often support more conservative legislation, will still be a factor in the newly elected Congress.
"You're not going to see the floodgates open and see every piece of populist tax-raising, business-unfriendly legislation just roll through."
Majority Rules? Not Always
Doug Kriner, a congressional expert and professor of political science at Boston University, said even with increased numbers in both houses, Democrats still won't always get their way.
"They will not get everything they want," he said, adding that in addition to the Blue Dog Democrats, some moderate Democratic senators from states such as Montana and North Dakota will still stand up to the majority.
"For Democrats to always prevail in Congress would demand a lot of party loyalty, which isn't always the rule of the Senate," said Kriner.
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Democrats One-Party ChangeThroughout history, Kriner said, the public perception of which is better -- a divided Congress or a unified one -- has wavered.
In the late 1980s and early 1990s, Americans feared that a divided government might lead to gridlock, said Kriner. But feelings changed during the mid- to late-1990s, when many Americans began to prefer it, arguing that the split between parties would "promote more moderate policies."
Kriner said that despite Sen. John McCain's assertions throughout the campaign that a unified Congress would be a bad idea, the public may now prefer a more unified Congress because of the widely held desire for change.
During President Franklin D. Roosevelt's administration, Zelizer recalls, the unified Congress forced the president to negotiate constantly between the Northern Democrats and the Southern Democrats.
"FDR managed to find bills that both sides could support, but often ended up watering down legislation because he didn't want to offend the Southerners," said Zelizer.
Some Legislation Will Benefit
Even though all liberal legislation won't be easily agreed upon, there are some measures that will likely benefit from the single-party rule in Congress.
Mathias says legislation regarding regulation of the financial services industry and the taxation of carried interest are two issues that are likely to benefit from Democratic majority rule.
Mathias said that issues like energy policy and agriculture policy – which is much more regional -- probably won't be helped that much by the Democratic majority.
"Democrats are naturally ideological, and as a party are interested in inclusion and broadening the participants in the democracy," said Mathias. "So they're bringing in outsider candidates more easily than the Republicans, and as a result they get a lot of people with a lot of different points of view."
Some of the newly elected senators, such as Democrat Kay Hagan in North Carolina, might have to answer to their traditionally more conservative constituencies, making it difficult to consistently vote with their parties, said Mathias.
"I don't think people will see a lock-step liberal agenda that everyone is worried about," said Mathias. "[These senators] are still going to have to respond to constituents who are very different from them -- and often times a lot more conservative."
Single-Party Rule: Buyer's Remorse?
So what will a unified Congress mean for a President Obama?
Some aspects could be worse than had a divided government, according to Mathias, who said Democratic senators may come to expect Obama's support.
"You could make the argument that it could make it more difficult to reach an agreement because they're all the same party," she said. "The senators may expect Obama to always agree with them because he's also a Democrat."
But even with those headaches, the sweeping victory on Election Day means that Obama will enter office with a stacked Congress and every opportunity to push through many of his legislative goals.
Boston University's Kriner reminds that even though Democrats will be celebrating their victory in the days to come, the win comes with a lot of responsibility.
"There's no doubt that this win will be a huge ego boost for the party and will bring them back to the glory days," said Kriner. "The GOP will have to regroup and decide what they'll do the next time around."
"But with the opportunity comes danger -- the danger of not living up to public expectations is a real problem for the Democrats," he said.
With the bad economy and the financial crisis coupled with two wars, the Democrats don't have an easy job ahead of them.
"They have a horrible hand dealt to them and it's not going to be easy," said Kriner.
"The public has said they want unified change and will now say to Congress, 'OK, we've given you the keys,'" said Kriner. "And if the Democratically-ruled Congress doesn't produce, they'll face an angry electorate in two years."