Let's start with what we already knew when the 114th Congress gaveled in this January: Republicans were cheering their control of both chambers for the first time in eight years, including a historic majority in the House of Representatives.
But they inherited a Congress suffering from serious morale problems. Congress had a reputation for being ineffective, unpleasant and unpopular. Americans told Gallup pollsters they thought car salespeople and telemarketers were more honest than their lawmakers in Washington, D.C. -- a distinction that remains at year's end:
Amid that dismal back drop, Congress arguably got even worse as the year went on. There were shutdown threats, leadership crises and drama from nasty 2016 presidential primaries seeping into its halls. And then suddenly, at the end of the year, things came together.
House Republicans got a new -- if initially reluctant -- leader in Speaker Paul D. Ryan (R-Wis.). Both sides can claim victories in a flurry of last-minute bipartisan legislation that funded the government, extended tax breaks and lifted the debt ceiling.
There are plenty of reasons to be pessimistic about Congress next year as well, but thanks to the sudden change of events in the House, lawmakers on both sides of the aisle will tell you there's at least a glimmer of hope things will be less contentious in 2016.
But to understand what might be to come, we have to first dissect what just happened. Here are five things we learned about Congress from this tumultuous year:
1. The House is still broken …
Consider these sobering statistics from Gallup: Those who pay attention to Congress actually like it less. In other words, it's not people who don't actually tune in who are dismissing Congress as a bunch of louts.
And since July, Republicans have actually given the GOP-controlled Congress lower approval ratings than Democrats and independents, according to a November Gallup poll.
It's not normal to have members of the party in control of Congress most upset with Congress. But maybe these voters are on to something. The story of 2015 on Capitol Hill is filled with congressional gridlock on just about every major issue, the government very nearly shutting down in October and the House leader's sudden resignation as his own members threatened to remove him.
A growing and emboldened group of 30 to 40 conservatives played a big role in all this by holding up or stopping legislation they didn't approve of. By refusing to back down from their demands, the group became so influential it eventually ushered Speaker John A. Boehner (R-Ohio) out of his job.
The Fix's Chris Cillizza has argued our current divided, outsider-driven political system is encouraging the drama. Lawmakers are able to take more hard-line stands without political consequences thanks to more polarized districts back home, while influential outside groups flush with cash are encouraging such behavior.
Adding to the challenges is a group of about 70-100 Republican lawmakers who are nervous about primary challengers because they are otherwise in safe districts. They joined the conservative cause on many votes this year, from not funding the Department of Homeland Security to standing firm against a debt limit increase. Congressional leaders had fewer tools at their disposal -- like earmarks for pet projects -- to entice members to vote differently.
These dynamics have been quietly forming and playing out for a few years , and in 2015 we finally saw the chaos burst to the surface.
2. … But it can hobble along
At least, the most optimistic of those in Republican leadership say so. They point to the spending bill and tax deal that Ryan and House Minority Leader Nancy Pelosi (D-Calif.) slapped together to avoid a government shutdown. It got a majority of votes from both parties, although congressional budget watchers mostly attribute the vote totals to goodies the leaders tacked onto the bill -- basically earmarks in everything but name.
And let's not forget that on his way out the door, a beleaguered Boehner managed to strike a budget deal with Pelosi that lifted the debt ceiling through 2016 -- taking a potentially disastrous default debate off the table for the presidential election.
Notice the figure central to both Ryan's and Boehner's deal-making: Pelosi. Even though House Republicans have one of the largest majorities since the Great Depression, Democrats played a significant role this year by helping pass just about every must-pass deal, sometimes even carrying the majority of "yes" votes.
As such, Pelosi had a lot of leverage to shape outcomes. We named her one of the spending deal's winners after Democrats secured major victories, including getting domestic spending increased by the same amount as military spending. Republicans got some things to brag about too, like lifting the 40-year crude oil export ban.
The back-and-forth is just what happens in a legislative body with a sizable minority -- or at least one empowered by a divided majority. "Welcome to divided government," Rep. Tom Cole (R-Okla.) told me last week.
And as long as conservatives in the House continue to split off from their party, a divided government is likely to be Congress's reality next year, too. Which means Ryan faces many of the same predicaments Boehner did -- the end-of-year agreements notwithstanding.
3. Sometimes, a fresh face helps
One of the most interesting storylines in Congress this year is the goodwill conservatives extended to Ryan, their new leader, even though he arguably didn't produce results that different from Boehner's.
Ryan managed to negotiate a spending bill with Democrats in the same manner and with largely the same outcomes that Boehner likely would have. But Ryan did it without earning the same kind of vitriol from the right flank of his party that Boehner likely would have. The group on the right didn't like the spending bill, and many didn't vote for it, but they didn't call Ryan names for negotiating it with Democrats.
Knowing he was at risk of being compared to the politically toxic former speaker during these negotiations, Ryan did his best to subtly draw contrasts with Boehner outside of them -- Boehner smokes and drinks; Ryan works out every morning. Boehner stacked powerful committees with his allies; Ryan opened the positions up to the whole House.
Cole told The Fix that Ryan also did a better job than Boehner explaining to Republicans why he was negotiating with Democrats and taking everyone's ideas into account -- even if they wound up on the cutting room floor.
Ryan might be different enough in style from Boehner that some conservatives skeptical of their party's establishment were willing to forgive the two men's similarities in substance.
On the other hand, it has only been two months.
4. Republicans aren't the only ones with partisan drama
A lot has been written -- including here on The Fix -- about the influence of the far-right on the Republican Party, pulling the party to the right both in Congress and on the campaign trail while rendering the House basically ungovernable.
That, in broad strokes, is true. But there are signs Democrats are also moving closer and closer to the extreme of their party, too.
Earlier this month, we named liberal leader Sen. Elizabeth Warren (D-Mass.) one of the winners of the Democratic presidential primary so far, as front-runner Hillary Clinton picks up on some of Warren's economic populist rhetoric. The populist Sen. Bernie Sanders (I-Vt.) is also having surprising success this year, for obvious reasons.
Nonpartisan tech start-up Crowdpac (the ones who recently matched up the 10 most liberal and 10 most conservative cities by campaign donors) tried to put numbers to such anecdotal evidence. The company analyzed who has been giving money to lawmakers and tracked lawmakers' votes since 1980. Here's what they found:
The findings, which combine political contributions and voting records of members of Congress, go back to our first point: Congressional lawmakers have little incentive to reach for the middle when politics is pushing them further and further apart.
5. Increasingly, the action isn't in Congress
Earlier this year, one of Republicans' first challenges in their new position of power was to try to stop the president's executive actions on immigration. They didn't. However, a multi-state court challenge has held up those same immigration actions to the point where they might not be implemented before President Obama leaves office.
A similar situation has played out with the president's 2010 health-care reform law. The House has voted more than 60 times over the past four years to repeal Obamacare. Such a bill has never made it to the president's desk.
By contrast, there have been not one but two challenges to the law that made it to the Supreme Court. Even though the court upheld the law both times, the legal challenges got further than the legislation ever could.
We could say the same thing for Republicans' attempts to roll back the Obama administration's regulations to cut power plants' emissions, which they haven't been able to stop in Congress either. But those regulations are facing a multi-state legal challenge. (In June, the Supreme Court narrowly ruled against the administration's attempts to regulate mercury from power plants.)
In short, trying to stop or reverse Obama's agenda has confounded congressional Republicans, and that failure been a major source of frustration for the increasingly influential grassroots faction of the party.
Perhaps trying to advance political agendas through this broken, partisan and often unpredictable Congress is the reason why.