Capitol Hill isn’t a happy or easy place to be these days, and several senators could be eyeing the exits ahead of 2016.

While no official retirement statements have come out of the upper chamber yet, it’s safe to assume that many politicians are using the holidays to ponder their future.

Here are 10 senators who could potentially step down after the 114th Congress.

Sen. Barbara Boxer Barbara Levy BoxerThe Hill's Morning Report - Presented by Facebook - Biden, Harris launch Trump offensive in first joint appearance Bottom line Polls show big bounce to Biden ahead of Super Tuesday MORE (D-Calif.)

Boxer’s fundraising efforts have lapsed, stoking speculation that the longtime liberal senator is ready to hang it up.

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According to her latest Federal Election Commission filings, Boxer has less than $150,000 in her campaign account after a quarter in which her contributions fell short of $12,000.

That’s in stark contrast to her fundraising efforts from the same quarter ahead of her successful 2010 reelection, when she raised $2.6 million and sat on more than $3.6 million.

Boxer, who is 74, told The Associated Press earlier this year that she’ll make an announcement in early 2015.

If she does retire, Democrats' deep bench of diverse potential candidates includes Lt. Gov. Gavin Newsom, Attorney General Kamala Harris, Los Angeles Mayor Eric Garcetti and former Los Angeles Mayor Antonio Villaraigosa.

Sen. David Vitter David Bruce VitterLysol, Charmin keep new consumer brand group lobbyist busy during pandemic Bottom line Bottom line MORE (R-La.)

Vitter announced earlier this year that he intends to run for governor of Louisiana in 2015 to succeed term-limited Gov. Bobby Jindal (R-La.).

Since it’s a year before he’d be up for reelection in the Senate, if he wins, he could retire from the Senate and appoint an interim replacement to his seat in the upper chamber. If he loses the governor’s race, he could still run for reelection to the Senate in 2016.

Analysts say Vitter, who coasted to reelection in 2010 despite previously having admitted to being a client to the infamous “D.C. Madam,” is the overwhelming favorite to take the governor’s mansion in a state that has turned deep red in recent cycles.

However, the Louisiana gubernatorial race is a jungle primary, so Vitter’s toughest challenge could come from another Republican. Strategists say Vitter would easily dispatch of any potential Democratic foes, but if none make it to the runoff, they say anything could happen between two Republicans going head to head.

Rep. John Fleming John Calvin FlemingTrump wants Congress to delay Census deadlines amid pandemic Meadows sets up coronavirus hotline for members of Congress The Hill's Morning Report - Iran strikes US bases in Iraq; Trump to speak today MORE (R-La.) has also expressed interest in the seat, and Rep. Charles Boustany Charles William BoustanyPartial disengagement based on democratic characteristics: A new era of US-China economic relations Lobbying world March tariff increase would cost 934K jobs, advocacy group says MORE Jr. (R-La.) has also been mentioned. Republicans in the state also have a deep bench of potential state-level candidates.

Sen. Marco Rubio Marco Antonio RubioFlorida senators pushing to keep Daylight Savings Time during pandemic Hillicon Valley: DOJ indicts Chinese, Malaysian hackers accused of targeting over 100 organizations | GOP senators raise concerns over Oracle-TikTok deal | QAnon awareness jumps in new poll Intelligence chief says Congress will get some in-person election security briefings MORE (R-Fla.)

Rubio’s Senate career is at a crossroads.

He’s been laying the groundwork for a presidential run, but Florida state law prohibits him from running for the Senate and White House at the same time. Unlike Sen. Rand Paul Randal (Rand) Howard PaulSecond GOP senator to quarantine after exposure to coronavirus GOP senator to quarantine after coronavirus exposure The Hill's Morning Report - Sponsored by National Industries for the Blind - Trump seeks to flip 'Rage' narrative; Dems block COVID-19 bill MORE (R-Ky.), who is seeking a work-around to the same conundrum in his home state, Rubio has said he won’t seek both.

That means if Rubio takes the presidential plunge, he’ll have to retire from the Senate.

If that’s the path he takes, Florida would become an instant toss-up. Democrats are already eyeing two House members from red districts in the state — Rep. Patrick Murphy and incoming Rep. Gwen Graham — as potential challengers to Rubio or whoever the GOP puts forth to run for the Senate in 2016.

Political watchers, meanwhile, have no idea whether Rubio will run for president. They believe he’s a rare political talent, but his mentor, former Florida Gov. Jeb Bush, is likely running for president, and the two share many of the same donors and supporters.

Rubio has maintained Bush’s decision won’t factor into his own, but polls show that most Republicans right now would side with Bush over Rubio.

Still, Rubio is a popular rising star in the party, and he has options beyond 2016. He could run for governor to succeed Gov. Rick Scott (R) in 2018, and Florida’s other Senate seat, currently held by Sen. Bill Nelson Clarence (Bill) William NelsonDemocrats sound alarm on possible election chaos Trump, facing trouble in Florida, goes all in NASA names DC headquarters after agency's first Black female engineer Mary W. Jackson MORE (D-Fla.), will also be up for grabs that year.

Sen. Joe Manchin Joseph (Joe) ManchinBiden promises Democratic senators help in battleground states Senate leaders quash talk of rank-and-file COVID-19 deal OVERNIGHT ENERGY: House Democrats tee up vote on climate-focused energy bill next week | EPA reappoints controversial leader to air quality advisory committee | Coronavirus creates delay in Pentagon research for alternative to 'forever chemicals' MORE (D-W.Va.)

Manchin, a centrist Democrat from a red state, has been vocal about his frustrations with gridlock on Capitol Hill and the leadership in his own party.

That could have him eyeing a return to his old job as governor of West Virginia, a post he held from 2005 to 2010.

“There is definitely that consideration," he told The Register-Herald in November. "If I don't see the opportunities to really help my country and my state, and things just stay the same and we continue to hear the rhetoric, if it's the same-old same-old, it's not a place I'd desire to be.”

"If there is an opportunity in West Virginia and the people would want me to come back home, I would definitely consider that move," he added.

The Hill reported earlier this year that Manchin gave generously to state officials from his campaign account in 2014, potentially laying the groundwork for a return there.

Democrats would be hard pressed to hold Manchin’s seat should he leave Washington.

In 2016, it will have been 20 years since West Virginia voted for a Democratic presidential candidate, and Republican Sen.-elect Shelley Moore Capito Shelley Wellons Moore CapitoSecond GOP senator to quarantine after exposure to coronavirus GOP senator to quarantine after coronavirus exposure Hillicon Valley: Zuckerberg acknowledges failure to take down Kenosha military group despite warnings | Election officials push back against concerns over mail-in voting, drop boxes MORE crushed her Democratic opponent in 2014 by nearly 30 percentage points.

Sen. Harry Reid Harry Mason ReidSenate Republicans signal openness to working with Biden Mellman: The likely voter sham Bottom line MORE (D-Nev.)

Reid has said he’s running for reelection and reports indicate he’s beginning to staff up, but would the 75-year-old outgoing Senate majority leader stand in for another fight if he was a long shot?

In 2010, Reid survived the Tea Party wave in large part because of the disastrous candidacy of GOP nominee Sharron Angle. But in 2016, he’ll be a top target for Republicans.

Reid is underwater among Nevada voters, and if Gov. Brian Sandoval (R-Nev.) jumps in, the longtime Senate Democrat would become an instant underdog.

Reid, who has more than $1.5 million in cash on hand, has experienced backlash from some centrists in his party who are ready for new leadership after November's losses.

Sen. Dan Coats Daniel (Dan) Ray CoatsFBI chief says Russia is trying to interfere in election to undermine Biden The Hill's Morning Report - Sponsored by The Air Line Pilots Association - Trump, Biden renew push for Latino support Former Intel chief had 'deep suspicions' that Putin 'had something on Trump': book MORE (R-Ind.)

Coats has retired once before, spending more than a decade outside of Washington before returning for a third term in 2010.

He’s expressed frustration with the gridlock in Congress, but earlier this year, he told The Elkhart Truth that a Republican majority would factor into his decision to run for reelection.

Republicans took the Senate in 2014, but that majority could be short-lived. Coats presently has less than $800,000 in his campaign account.

Sen. John McCain John Sidney McCainMcSally says current Senate should vote on Trump nominee Say what you will about the presidential candidates, as long as it isn't 'They're too old' The electoral reality that the media ignores MORE (R-Ariz.)

The 2008 GOP presidential nominee has openly mulled retiring when his term ends in 2016.

“The president and I, he's in his last term, I'm probably in mine, the relationship we have had over the past three years is quite good,” he told The Wrap in an interview last year, adding that he didn’t want to be “one of these old guys that should’ve shoved off.”

He’s since changed his tune, telling The Arizona Republic that he’s “seriously considering” and “leaning towards" running for reelection.

Still, the 78-year-old knows what kind of challenges lie ahead. He’s acknowledged that he’ll likely get a primary challenger from the right, and if that’s not something the no-nonsense five-term senator wants to deal with, he could shove off sooner rather than later.

Sen. Chuck Grassley Charles (Chuck) Ernest GrassleySenate Republicans face tough decision on replacing Ginsburg What Senate Republicans have said about election-year Supreme Court vacancies Biden says Ginsburg successor should be picked by candidate who wins on Nov. 3 MORE (R-Iowa)

Grassley told a public TV station in Iowa earlier this year that he intends to run for reelection in 2016. He said that with Sen. Tom Harkin Thomas (Tom) Richard HarkinThe Memo: Trump attacks on Harris risk backfiring Ernst challenges Greenfield to six debates in Iowa Senate race Biden unveils disability rights plan: 'Your voices must be heard' MORE (D-Iowa) retiring at the end of the year, he didn’t want to leave the Hawkeye State with two junior senators.

Still, Grassley would be pushing 90 by the end of his next term, but he proved in 2014 he can still handle the rigors of the campaign trail. He crossed the state on behalf of Republican candidates, and he’s an avid runner to boot. The Republican has more than $1.7 million in his campaign account.

Sen. Patrick Leahy Patrick Joseph LeahyBattle over timing complicates Democratic shutdown strategy Hillicon Valley: Russia 'amplifying' concerns around mail-in voting to undermine election | Facebook and Twitter take steps to limit Trump remarks on voting | Facebook to block political ads ahead of election Top Democrats press Trump to sanction Russian individuals over 2020 election interference efforts MORE (D-Vt.)

Leahy told reporters at the end of 2013 that the government shutdown convinced him that he needed to run again to ensure that there are enough “grown ups” in Washington to run things.

But at 74 years old and with four decades in Congress behind him, he’s among the most senior members in the upper chamber. He’ll also be losing his chairmanship on the Senate Judiciary Committee when Republicans take over in January.

If he did step aside, his seat would likely be a safe one for Democrats in liberal Vermont.

Sen. Barbara Mikulski Barbara Ann MikulskiForeign policy congressional committees need to call more women experts Lobbying World Only four Dem senators have endorsed 2020 candidates MORE (D-Md.)

Mikulski, 78, will also be losing a gavel this year.

However, the first woman to chair the Senate Appropriations Committee appears committed to seeking a fifth term.

She has sought to rally Democrats in Maryland after the party suffered a devastating loss in the race for the governor’s mansion. She is also looking to appoint a party “loyalist” to ease her transition into the 2016 election cycle.

She has less than $900,000 in cash on hand.