The retirements of longtime Sens. Christopher Dodd, D-Conn., and Byron Dorgan, D-N.D., will likely chill the liberal agenda of the Democratic majorities in the House and Senate as they seek to avoid widespread losses in 2010.
Political experts believe the prospect of significant Republican gains in November will leave Democrats divided over what to do next when it comes to passing their biggest legislative priorities, including global warming legislation and an immigration reform bill.
"Obama is going to make the argument that now is the time to act," said University of Virginia political science professor Larry Sabato. "But the congressional Democrats who are threatened are going to be saying, 'Sorry Mr. President, we have given you enough tough votes for this term.' "
The bills Democrats are most likely to abandon in the face of this daunting political landscape are the global warming bill, which would cap carbon emissions and fine those who pollute, and legislation that would make it easier for employees to unionize. Immigration reform, which was already considered unlikely, will also come off the table, political analysts say.
Veteran Democratic strategist Doug Schoen believes that in the short term, Democrats will push hard to pass their health care reform bill, preferably in the coming weeks.
"Longer term, they will have to move to the center, otherwise they will face a tsunami," he said.
Experts are predicting gains of 20 seats or more in the House for the GOP. And Dorgan's retirement puts at least nine Senate Democratic seats in reach of Republicans. If those predictions are close to the mark, Democrats in both chambers will have to work with a much smaller majority, which will make it harder, if not impossible, to move their agenda.
Lawmakers may look to Dorgan as a warning sign. The three-term senator watched his once-high poll numbers plummet in recent months as the Democratic health care bill made its way through the Senate.
In a hypothetical matchup with Republican Gov. John Hoeven, Dorgan trailed by 22 points. In the same poll, conducted in December by Rasmussen Reports, 64 percent of voters said they opposed the sweeping Democratic health care reform bill that Dorgan voted for.
The Cook Political Report now lists Dorgan's seat in the "Lean Republican" category.
In the House, there has been a string of Republican and Democratic retirements, but it is the GOP that stands to gain in 2010, according to election analysis data. The Democrats who are calling it quits are vulnerable moderates from districts that lean Republican.
There are many more politically vulnerable House Democrats who have been unwilling to sacrifice their jobs by voting for legislation that is unpopular with their constituents. That isn't likely to change.
"There are still a core group of Democrats here who are not suddenly going to lay down and roll over because of Democratic retirements," political analyst Stu Rothenberg said. "If anything, it will only enhance their position, and leaders will have to find a way to pass bills."