While Senate Democrats and Republicans appear content to complete the 110th Congress using the same partisan script they followed for much of the past two years, senior aides in both parties agree that come January, the chamber could see at least a temporary return of bipartisanship and comity that was sorely lacking during much of the Bush administration.

Democratic leaders hope to use the first several months of 2009 warming Republicans to the idea of working with a Democratic White House and solid majorities in the House and Senate.

And President-elect Barack Obama can likely expect a three-to-four-week grace period during which Republicans will show great deference to his nominees and early legislation that he and Majority Leader Harry Reid (D-Nev.) look to push through, according to one Republican aide.

“I don’t think anyone has any intention of meeting Obama at the door with a whole list of partisan complaints,” the GOP aide said. “Most of our Members believe he’s gotten off to a good start. … Particularly given the state of the economy, everyone is interested in achievements.”

Likewise, Senate Democrats are charting a course for the first 100 days that will lean heavily on easy-to-pass bills and measures that, with their expanded majority and expected support from GOP moderates, will allow them to head off filibusters.

That familiar list includes a children’s health insurance bill, a measure to expand research using embryonic stem cells and legislation to ensure equal pay for equivalent jobs, among other things.

“The idea is that these are things we can have ready for Obama to sign into law in his first few days in office,” said one senior Senate Democratic aide. “It will set the tone that we did this in a bipartisan way. … And it will give us an idea of who we can work with or who’s standing on partisan, ‘us versus them’ ground.”

The aide said even Republicans who may vote against those measures or other leftovers from the 110th Congress could be included on a list of people who are at least willing to engage in the negotiating process.

And, at this point, Republicans said that list could be fairly lengthy.

On the messaging front, Republicans are expected to keep their powder dry for at least the first few weeks of the new administration. One aide pointed out that national Republicans have not gone into partisan attack mode over Obama’s nominees, including picks such as the attorney general designee, Eric Holder, who played a role in former President Bill Clinton’s controversial pardon of Marc Rich.

“We have absolutely no intention of getting off to a partisan start,” the aide said. “Now, these people are not going to get free rides … but banging away on them early on for partisanship’s sake has not happened.”

A second senior GOP aide said the economy has given Obama something of a pass early on, and that at least in the first few weeks or months of his administration will continue to give him cover. Public concern with the economy has made it possible “for him to talk about more spending in one speech than most of us would talk about in an entire year of appropriating,” the aide said.

While warning they will continue to use filibusters and other procedural tactics to protect their rights as the minority, Republicans said they hope the new Congress will not turn into the kind of running skirmish between the two parties that made it impossible for almost anything to pass over the past two years.

Significantly, that could mean an end to the routine use of filibusters on every procedural vote during the process of considering legislation. Over the past two years, Senate Minority Leader Mitch McConnell (R-Ky.) has used filibusters of motions to proceed, motions to end debate and other procedural votes to slow or halt bills Republicans opposed. Reid and Democratic Senatorial Campaign Committee Chairman Charles Schumer (N.Y.) used those efforts to label Republicans as obstructionists during the campaign.

And while Reid and Schumer ultimately fell short of gaining a 60-vote majority, Republicans acknowledged that the obstructionist tag hurt them in the election.

“The trick is to raise hell at the right time, not to raise hell every week. There will be times when we need to draw a line in the sand … but there’s a really big danger in doing it too soon or all the time,” one Republican said.

Internally, Republicans said they expect to see a more engaged and energetic GOP leadership operation than in the previous Congress. With McConnell, Senate Republican Conference Chairman Lamar Alexander (Tenn.) and other members of leadership up for re-election this past cycle, it was at times difficult for leadership to focus its energies solely on the Senate.

Additionally, Republicans said the absence of President George W. Bush will make it much easier for McConnell to rally his smaller team around common themes. Republicans will have “a more robust leadership. Last year was very different with the Bush administration … it’ll be much easier to define ourselves without Bush around,” the aide said.

McConnell and Alexander are also expected to press more of their Conference into duty leading on issues they have interests in. While in the majority — or even with last year’s one-seat deficit — it was easy for some “backbench” Republicans to stay on the sidelines of major policy fights, even in cases in which they had an intense interest.

Additionally, moderates often found themselves on the outside of internal policy fights in recent years as their numbers diminished.

But with their overall numbers significantly thinned, Republicans will likely have to field their entire team and will not be able to exclude some Members over their policy positions. “The reality that we have a minority of 42 means that we have to work as a minority of 42 as best as we can … you do not acquire more seats by excluding people from the process,” one Republican said.

A Republican aide agreed. “Anytime your numbers are fewer, the Members you do have are going to play a bigger role.”

Senate Democrats said Reid will put a premium on fulfilling Obama’s campaign promises to change the way Washington works — and that effort will give Democrats a feel for which Republicans are potential dealmakers.

“How do you smoke them out?” asked the leadership aide. “By following through on the pledge to change the way business in Washington is done.”

With a Republican-led White House unwilling to negotiate on most issues and a minority reluctant to allow Democrats to score any accomplishments, Reid gave as good as he got in the partisan warfare that nearly paralyzed the Senate for the past two years.

But aides said a softer, gentler Reid is likely to emerge with a beefed-up majority and an ally in the White House during the 111th Congress.

“Now that he doesn’t have to serve as a foil for the president, he can go back to what he does best, and that’s cutting deals,” the leadership aide said.

The aide acknowledged that Reid and Democrats as a whole will have to prove to Republicans that they’ve turned the page, perhaps by allowing more GOP amendments on the floor.

“I expect there’ll be give on both sides,” the aide said.

Republicans remain skeptical about the long-term prospects for the two parties to coexist without intense partisanship, particularly given Reid’s penchant for inflammatory, off-the-cuff remarks.

“Reid’s ability to turn anything as red hot as possible in about 15 seconds is something I don’t think the Obama people have taken into account,” one Republican said.

A GOP Senate aide agreed, warning that like Republicans before them, Democrats will eventually over-reach. “We have to let them do some things. But over time they’re going to get crazier … and eventually they’ll have their own Terri Schiavo, but in their case they’ll be killing people with sprained ankles.”