Sen. Carte Goodwin looked like any other Senator on Tuesday as he stepped forward to the clerk’s desk to cast his first vote. The West Virginia Democrat will have a Member’s pin, an office in the Russell Senate Office Building and all the perks accorded a U.S. Senator.

But Goodwin, like several of his colleagues, won’t be getting too comfortable in his new digs.

Call them caretakers, seat-warmers, placeholders or lame ducks. Just make sure you call them Senators.

The Senate has four Members holding seats they do not expect to run for: Goodwin, who will fill in between the death of Sen. Robert Byrd (D-W.Va.) and a special election this fall; Sen. Roland Burris (D-Ill.), who took now-President Barack Obama’s place; Sen. Ted Kaufman (D-Del.), who is serving in the stead of his longtime boss, now-Vice President Joseph Biden; and Sen. George LeMieux (R-Fla.), who succeeded former Sen. Mel Martinez (R) when he resigned.

There haven’t been this many since 1954. But it’s certainly not unprecedented: Of the 188 appointments since 1913, more than a third of the appointed Senators did not go on to seek the seat they held.

Not all caretakers approach their tenures the same way. Burris, for example, initially planned to run for a full term, but the scandal that led to his appointment created a cloud that made a campaign untenable, and he succumbed to pressure from party leaders to drop his bid. Kaufman, on the other hand, took the job in 2009 knowing he would step aside two years later.

Whether they’re reluctant or content to be short-timers, these Senators describe gaining temporary access to one of the world’s most exclusive clubs as a privilege. And, they say, the job is what you make of it.

“It is a special honor and a special challenge,” says former Sen. Paul Kirk, the longtime aide to the late Sen. Edward Kennedy (D-Mass.) who filled the seat for less than five months after Kennedy died in 2009. Appointed Senators with no designs on a permanent spot in the Senate “have almost a unique responsibility because they won’t ever face the electorate. Failure is not an option.”

Thomas Mann, a Congressional scholar at the Brookings Institution, says such Senators play varying roles. “It depends on the circumstances of the appointment, the quality of the person and the nature of the work that they do,” he says.

Some bristle at the very use of the “caretaker” label. “I don’t like to call it that,” says LeMieux, a longtime chief of staff to Florida Gov. Charlie Crist, the man who appointed him and who is now seeking the seat for himself. LeMieux insists that the brevity of his tenure calls for more urgency, not less.

“My motto around the office is that we’re going to get six years out of 16 months,” he says.

Burris, who has played a low-key role in the chamber, says he would counsel the newly arrived West Virginian to savor his short stint. Goodwin should “learn all that he can and cherish the opportunity to serve in the greatest deliberative body in the world,” Burris says.

Kaufman is perhaps the greatest anomaly and the best example of his species. He was chief of staff to Biden for about 20 years and for decades has taught classes about the Senate at Duke University. That history meant he brought a knowledge of the Senate’s intricacies and issues that colleagues say allowed him to immediately slip into a senior role.

“He’s so smart that people really look to him,” says Sen. Tom Carper (D-Del.), who serves alongside Kaufman. “He hit the deck running.”

Kaufman, who has focused on financial regulatory reform and the federal work force during his tenure, says there’s a misconception about the role of a temporary Senator: that they are free to do whatever they fancy since they are untethered from political pressures.

If he were facing voters in November, “there is not a single thing I would do differently,” he says. The major difference, he says, is that he is free from the time-consuming tasks of campaigning and political fundraising, and therefore he can spend more energy on Senatorial duties. Kaufman says he even counseled Burris about whether the Illinois Democrat should run for a permanent Senate seat.

“I said there are two things you can do. You can run and spend 50 to 60 percent of your time campaigning and maybe get another six years here, or you can spend 100 percent of the time you have being a U.S. Senator.”

Colleagues might envy interim Senators’ freedom from the endless rounds of fundraisers, solicitation phone calls and campaign travel. But the greatest perk might be the opportunity not just to watch history being made — even from the close vantage point of a staffer — but to live it for a brief time.

“He’s got the greatest job going,” Carper says of Kaufman. “To think, ‘I get to be a Senator for two years, travel the world, and vote on historic bills like the health care bill.’ … What’s not to like about that job?”

Kaufman points to a wall of pictures that tells the story: his wife flanked by Michelle Obama and Jill Biden; Kaufman, surrounded by his children and grandchildren, after carving his initials into his Senate desk, a tradition that dates back to the 1900s.

“To be able to make the people you love so happy is a true blessing,” he says, “and to try to do some good while you’re at it.”

For Kaufman, 71, and Burris, 72, a stint in the Senate isn’t a steppingstone to future elected office. But LeMieux, 41, and Goodwin, the youngest Senator at 36, could have long political futures in front of them if they want them. In fact, LeMieux is rumored to be interested in running against Sen. Bill Nelson (D-Fla.) in 2012, and Goodwin could run to succeed Rep. Shelley Moore Capito (R-W.Va.) in two years if the Congresswoman decides to run for higher office.

Mann notes that serving as good custodians of their seats is a way to cement loyalty to the governors who appointed them and give them good name recognition along with a platform, however brief.

“And it’s kind of a kick, don’t you think?”