Hillary Clinton, who is expected to unveil her second presidential campaign early next year, is poised to become the dominant political figure of 2015. What we don’t yet know is how seriously she’ll be challenged for the Democratic nomination, whether she’s learned the right lessons from her failed 2008 bid and how the former secretary of state will deal with her former boss, Barack Obama.

The Republican field for the White House is wide open, with no clear front-runner or heir apparent. Jeb Bush claimed a lot of oxygen with a surprise announcement that he’ll “seriously consider” a run. But there are many reasons to believe today’s GOP won’t nominate him, even if he raises more money than everyone else.


Obama enters the final two years of his presidency with a Republican-controlled Senate, further limiting his ability to pass big legislation. But perhaps term limits and a foil on Capitol Hill will liberate him, as seen with recent executive actions on immigration and relations with Cuba.

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GOP leaders are like the dog that has finally caught up with the car. Now, dominating both chambers of Congress, they must govern.

Here’s our look at the 15 biggest open questions for 2015 – the known unknowns:

1. Can Hillary change?

Iowans thought Clinton took them for granted in 2008; her third-place finish, behind then-Sen. John Edwards, was the start of her downfall. The presumption of inevitability rubbed voters the wrong way, and the lack of accessibility alienated reporters. Her last campaign was marked by epic staff infighting; she came across as poll-driven and triangulating; and Bill Clinton’s lack of message discipline made him a liability.

Hillary insiders promise this time will be different. Clinton has been meeting with potential managers, and at least one is now out of the running. The presumed favorite is 35-year-old Robby Mook, who has led the Democrats’ House campaign committee and managed Terry McAuliffe’s successful Virginia gubernatorial effort last year.

Can Mook prevent factions from forming on the campaign? Will Clinton be willing to not just bring on fresh blood but empower new advisers to make decisions?

2. Who emerges as the left’s Hillary alternative?

As ominous as the Clinton juggernaut seems, 2008 showed that there are good reasons to take her on anyway. Just ask Barack Obama.

That’s why someone will run against Clinton from the left; the question is what caliber of candidate they’ll be.

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Progressives love Elizabeth Warren, and the first-term Massachusetts senator loves buzz that she might challenge Clinton. It’s why she always responds to questions about 2016 in the present tense: “I’m not running,” she says. But it seems likely that Warren is not going to run; she’s just smartly capitalizing on the platform that she’s been given.

Jim Webb, the former one-term Virginia senator and first serious candidate in either party to create an exploratory committee, holds many centrist views, but he’s been cheered on by lefty outfits like The Nation for his anti-war stance.

Sen. Bernie Sanders (I-Vt.), a self-identified Socialist who caucuses with Democrats, has been traveling to the early states, including an Iowa pilgrimage earlier this month. He could inject some of his pet issues, but the white-haired 73-year-old is not a serious contender for the nomination.

Maryland Gov. Martin O’Malley has positioned himself as an unapologetic, bleeding-heart liberal. He’s worked for years to cultivate relationships in early states and may wind up as the most serious bet.

Vice President Joe Biden would be a formidable challenger and could emerge as a contender if Clinton shocked the political world by passing on a bid. But he isn’t taking steps to challenge Clinton if she runs.

3. How far will Hillary distance herself from Obama?

Clinton will likely be forced to walk a tightrope: How does she sustain the support of Obama’s African-American and progressive constituencies — which turned out in droves to back the president in 2012 and 2008 — without being pegged as Obama’s third term? The president has seen an uptick in his approval rating from the low 40s into the mid-to-high 40s, but more Americans still disapprove of his job performance.

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Clinton just offered public backing for Obama on his Cuba and immigration moves. But earlier this summer, Clinton described Obama’s decision not to back Syrian rebels early on as “a failure.” She bluntly chastised the administration’s self-described foreign policy doctrine. “‘Don’t do stupid stuff’ is not an organizing principle,” she told the Atlantic.

How far Clinton tacks to the left is a direct function of how serious her primary competition becomes. No one can compete financially, but someone who can inspire activists — or point out where she’s not in line with the base — will cause heartburn in New York’s Westchester County, where the Clinton campaign is likely to be headquartered. Watch how she handles an issue like trade. She supported NAFTA in the 1990s, but she also needs to shore up union support — and the rank and file are increasingly hostile to free-trade agreements being pushed by the Obama administration.

4. Does Jeb scare anyone off from running?

Bush may be a flash in the pan. His positions on immigration and Common Core, combined with his establishmentarian temperament, will make it hard to win over the swath of conservatives who make up big portions of the primary electorates in key early states. The former Florida governor has said he is willing to campaign in a way that wins him the general election but could cost him the nomination, something columnist George Will wrote this weekend is akin to a baseball player trying to steal first base.

Even if Bush does not go the distance, he may have a profound impact on the field of Republican candidates.

Florida Sen. Marco Rubio publicly insists that Bush’s announcement has no bearing on his own calculus about whether to seek the presidency or run for a second term in the Senate. But Bush’s half-entrance makes it much harder for a Rubio campaign to get off the ground. Rubio served in the Sunshine State’s legislature when Bush was governor, and their donor networks overlap. It’s conceivable he could challenge his old mentor, but he could also take a pass and be well positioned for 2020 or as a vice presidential pick.

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Many believe Jeb Bush’s seriousness was a factor in Ohio Sen. Rob Portman announcing that he would run for reelection instead of president earlier this month. Another Ohioan, Gov. John Kasich, would like to run for president, but he is much less likely to mount a campaign with Bush in the field.

Mitt Romney has told donors over the past few months that he’s thinking about running a third time. He feels no need to defer to Bush, but Bush’s move has already translated into less clamoring for Mitt within establishment quarters.

5. What is Rand’s ceiling?

Kentucky Sen. Rand Paul is a much savvier politician than his father, former Rep. Ron Paul (R-Texas). The younger Paul spent the year earning positive media coverage for reaching out to nontraditional constituencies like African-Americans and young people. But he’s also worked to court major donors and build a big-dollar money machine his dad never had for his presidential bids.

The question is whether an outspoken libertarian can win the GOP nomination. Assume he starts with his father’s 2012 base of support — 21.4 percent in the Iowa caucuses, 22.9 percent in the New Hampshire primary. How much can he build onto that?

The younger Paul has toned down what critics see as isolationist foreign policy views, coming around on foreign aid to Israel, for instance. But it’s easy to see a major donor like Sheldon Adelson pouring millions into a super PAC aimed at stopping Paul — even if the ads it runs don’t focus on the senator’s views of America’s place in the world.

6. Can Christie get his outbursts under control?

New Jersey Gov. Chris Christie spent much of 2014 trying to put the Bridgegate scandal behind him. He just had a successful run as chairman of the Republican Governors Association, and he remains popular with the tri-state money crowd.

At this point, he might be his own worst enemy. The very shtick that established him as a national figure threatens to undo him if he’s not more disciplined.

Many Republicans worry that Americans won’t want to entrust the nuclear launch codes to a guy who flies off the handle for no good reason. Liberal activists have found it way too easy to goad Christie. Indeed, one of the (many) reasons Romney did not seriously entertain Christie as his 2012 running mate was his temperament. His vetters made Romney a DVD of Christie’s most-painful-to-watch YouTube moments.

Christie has shown some impressive self-control in his personal life, losing an estimated 100 pounds since lap-band surgery. Can he shed some of the edge off his political persona?

7. Will the Republican play to limit presidential debates work?

The Republican National Committee believes Romney lost in 2012 partly because of the glut of primary debates — 20, in total — that forced him to the right and gave plenty of cringe-worthy sound bites to the other side (e.g. endorsing “self-deportation” and trying to bet Rick Perry $10,000).

The RNC has created a panel to choose the timing, location and media partners of the 2015-2016 debates. They want to cut the number of meetings in half, start later (September 2015, instead of May 2, 2011) and insist that conservative panelists join moderators from the mainstream media. Candidates who participate in non-sanctioned debates will not be allowed into sanctioned ones, according to rules passed at a meeting this past spring.

But it’s hard for candidates to refuse to participate in a debate hosted by the Des Moines Register in Iowa or the Union Leader in New Hampshire, even if it’s not officially sanctioned. There is also an incentive for candidates with less money to debate as much as possible so they can earn free media. Over the years, this dynamic has led to a proliferation of debates.

An RNC spokesman said Monday that the committee hopes to make a detailed announcement about a debate plan at its winter meeting in San Diego next month.

8. Does the Supreme Court invalidate the Obamacare subsidies?

The justices have agreed to hear a legal challenge on whether the Affordable Care Act allows the federal government to give millions of people tax credits to buy health insurance. Plaintiffs argue that the subsidies can be given only to those who live in states that have created their own health exchanges, which would mean that residents of more than 30 states do not qualify.

In 2012, Chief Justice John Roberts offered the swing vote that upheld the health law. It’s conceivable he could flip over this subsidy question, which would make Obamacare unworkable, forcing Congress to take action and potentially opening the door to a major rollback of Obama’s signature achievement.

The court will hear oral arguments in March and hand down a decision in June.

9. Will Boehner’s life be easier?

When Speaker John Boehner returns to Washington next week, Republicans will control 247 seats in the House, giving him his party’s largest majority in 86 years.

The Ohio Republican is going to quickly figure out whether that matters. His new House Republican Conference is made up of a large pocket of moderate, get-things-done Republicans who can help Boehner ditch his nettlesome right flank.

What does Boehner want to do? He hasn’t yet said, but he’ll have no shortage of tough issues to deal with. He’ll have to pass a bill to fund the Department of Homeland Security in February, and he has promised to fight Obama’s unilateral changes to the enforcement of immigration laws. The debt ceiling must be lifted by the fall. The speaker still is holding out remote hope for big action on immigration and tax reform.

The House GOP ranks have given Boehner advisers hope that he can finally cast aside the shut-down-the-place crowd. The clearest sign of Boehner’s support will come in early January, when the House elects its speaker. Boehner can afford to lose the support of only 29 Republicans.

10. Can McConnell control his conference?

Incoming Senate Majority Leader Mitch McConnell, likewise, is in a tough spot. He wants to show that Republicans are not just “the party of no” and can govern constructively after eight years in the minority. But he also needs to show his young, upstart members that he’s serious about advancing conservative principles, even if Republicans are six seats short of a filibuster-proof majority and Obama can veto any legislation that passes Congress.

McConnell’s top priority will be holding the Senate in the 2016 elections. Republicans must defend seven Senate seats in states Obama carried twice — including blue states like Illinois and purple states like New Hampshire, Pennsylvania and Wisconsin — in a year with presidential-level turnout. The leader needs to help give these vulnerable incumbents bills and accomplishments on which they can run.

But he also must grapple with the political needs of the three potential presidential candidates in his caucus. McConnell has publicly said he supports Paul, his home-state junior senator. Texas Sen. Ted Cruz, who angered Republican members with a constitutional point of order during the lame-duck session, will also be using the chamber as a platform to establish himself as the most conservative candidate in the field.

11. How often will Obama break out the veto pen?

Republicans have the votes to pass a bill pushing ahead the Keystone XL pipeline, which narrowly failed during the lame-duck session. Obama has not said what he’ll do, but that could become the first major veto of his presidency.

In an interview with NPR that aired Monday, Obama defiantly promised to veto any bills that roll back “gains” he’s made on health care and the environment.

“I haven’t used the veto pen very often since I’ve been in office, partly because legislation that I objected to was typically blocked in the Senate even after Republicans took over the House,” the president told NPR. “Now I suspect there are going to be some times where I’ve got to pull that pen out.”

The over-under is 11 — that’s the number of bills Bush vetoed in his final two years as president.

How many Senate Democrats — particularly those up for reelection in red states in 2018 — will join onto filibuster- or veto-proof coalitions that force Obama’s hand?

12. Will Democrats finally get credit for the booming economy?

The unemployment rate is 5.8 percent. A gallon of gas costs less than $2.50 per gallon. The Dow just hit a record high. The economy grew at a 5 percent clip in the third quarter, the best three-month period in more than a decade. But the great news has not registered with a majority of Americans, who still feel anxious and worried the country is on the wrong track.

Democrats have been reluctant to trumpet the great news because so many people are still hurting. Republican operatives believe their opponents made a huge mistake this year by not talking more about the economy.

National exit polls showed that just 32 percent of those who voted in the midterm elections believed the economy is getting better. Four out of five voters worried about the country’s current economic condition, and about 60 percent of them voted Republican. The GOP won two-thirds of the 70 percent of voters who thought the economy was either not so good or poor.

Democratic strategists fear that congressional Republicans will try to claim credit for the good economic news. The White House plans a renewed offensive to tout what the president calls “America’s resurgence,” and administration officials hope that an increase in real wages — seen in the last jobs report — will help lift Obama’s numbers.

13. Will Obama put more “boots on the ground” in Iraq?

After taking heat for saying he did not have a “strategy” to deal with the Islamic State, the president ordered airstrikes and has sent more “military advisers” to Iraq. Obama’s actions have helped put the radical Islamist group on the defensive, but if problems flare up Obama could be presented with difficult choices about committing real combat personnel to the region.

Obama never wanted to be a wartime president, and he’s reluctantly sent more troops to Afghanistan beyond when he hoped to be out of the country. The administration celebrated the formal end of the combat mission in that country this weekend. Obama noted in a statement that there were 180,000 American troops in Iraq and Afghanistan when he took office, and there are now fewer than 15,000.

Committing more forces into the war-torn Middle East would inject foreign policy into the presidential campaign just as it heats up. On the GOP side, Paul would likely be an outspoken critic of sending troops, but other Republicans would conceivably back the president — depending on what precipitated a potential crisis. Clinton, meanwhile, could be in a tough spot because it would highlight her original support for the Iraq War.

14. Will Brian Sandoval challenge Harry Reid?

The Republicans’ most-desired 2016 down-ballot recruit is Nevada Gov. Brian Sandoval, a popular, relatively moderate Hispanic who was formerly state attorney general and a federal judge. Fresh off winning reelection by a 46-point margin, Sandoval is by far the party’s best hope of taking down incoming Senate Minority Leader Harry Reid.

But Sandoval has seemed somewhat reluctant, even as Republican senators are lining up to urge him on and polls show Reid beatable. He knows that the five-term senator is a ruthless campaigner who can raise virtually unlimited amounts of money, directly and through the technically independent Senate Majority PAC. Reid has backing from many in the state’s gaming industry and other advantages that come with three decades of incumbency in the Silver State. The election will also be during a presidential year, with higher Hispanic turnout.

That all makes Reid tough to oust, despite his poor poll numbers. Still, if Sandoval gets in, Nevada will be the marquee Senate race of 2016. If he doesn’t, Reid would have an easier path to a sixth term.

15. Will Senate retirements put any seats in play?

Democratic retirements were major reasons Republicans took control of the Senate this year. They allowed the GOP to pick up seats easily in Montana, West Virginia and South Dakota but, most crucially, liberal lion Tom Harkin’s retirement made it possible for Republican Joni Ernst to win in Iowa. Harkin would have coasted to another term if he’d stuck around.

Republicans are much more likely to hold their majority if they can prevent incumbents in potentially competitive states from stepping down.

McConnell is expected to set a deadline for when his senators should announce if they’re not running again, but National Republican Senatorial Committee chairman Roger Wicker has predicted that there will be no GOP retirements.

The most buzzed-about potential departures are in solidly blue or red states where the other side would be hard-pressed to win. Democrats should easily hold onto seats in California and Maryland if Barbara Boxer and Barbara Mikulski call it quits, respectively. Republicans should keep a Louisiana seat if David Vitter is elected governor next year.

Longtime incumbents who had been on possible retirement lists, like Arizona Sen. John McCain or Iowa Sen. Chuck Grassley, are taking active steps to run. Republicans who could opt to retire and leave the party in a lurch include North Carolina Sen. Richard Burr or Indiana Sen. Dan Coats. If Rubio ran for president and not reelection — he’s said he won’t run for both simultaneously — the Florida Senate race would become a jump ball.

Jake Sherman contributed to this report.