The gubernatorial partisan shift is also arguably among the most underrated to occur during President Obama's time in office. Republicans have slowly taken over the state's top jobs and now have "an absolute stranglehold" on the governors' offices, holding 64 percent of them, writes The Fix's Chris Cillizza.
So you can expect to hear more about governors and their political power in 2016. In Times Square fashion, we're counting down five governors who, for better or for worse, held our attention in 2015:
5. New Mexico Gov. Susana Martinez (R)
When your year ends having to defend what you threw off a hotel balcony — snowballs, not bottles, apparently — you've clearly had an interesting 2015.
The New Mexico governor made headlines just before the Christmas holiday after police said she was drunk in a Santa Fe hotel room where they were responding to complaints of noises and guests throwing bottles off the fourth-floor balcony.
Martinez denied both that she was drunk — her staff said she had one cocktail after the governor's holiday party earlier that night at the hotel ballroom — and that anyone threw bottles off the balcony. But it was the latest embarrassing incident for a governor with national appeal. Martinez, elected with 57 percent of the vote to her second, four-year term in 2014 in a blue state, was seen as prime vice presidential material for a party struggling to make inroads with Hispanic voters and women.
She's since become more of a punchline among some GOP elites in D.C. The holiday party debacle compelled The Post's James Hohmann to write recently: "Making it in Santa Fe is not the same as making it in Washington."
4. Indiana Gov. Mike Pence (R)
Like it or not, the Indiana governor was on the front lines of the gay rights vs. religious freedom battle this spring when he signed a controversial religious objection bill into law.
The law, which came as momentum for same sex marriage picked up rapidly, prohibits state and local laws that "substantially burden" people's abilities to follow their religious beliefs. Critics, including Apple CEO Tim Cook and Star Trek star George Takei, argued it would give business owners who don't want to serve LGBT people, such as wedding cake bakers or photographers, license to discriminate.
Pence repeatedly defended the law, saying it was not unlike a federal version that would allow the courts to decide what could be defined as a legitimate religious objection.
"If I saw a restaurant owner refuse to serve a gay couple, I wouldn’t eat there anymore. As governor of Indiana, if I were presented a bill that legalized discrimination against any person or group, I would veto it," he wrote in a Wall Street Journal op-ed.
Pence ultimately backed down slightly from the high-profile fight when he signed a revision to the law that specifically bans discrimination based on sexual orientation or gender identity, one of the first religious objection laws to specifically mention those two things.
However passionately he felt about the religious objections law, the debate over the measure ultimately damaged Pence's national prospects. Recruitment calls for him to run for president faded, and his approval rating dropped from the 60s before the religious freedom drama to 45 percent.
Pence is up for reelection in 2016.
3. California Gov. Jerry Brown (D)
From gun control to climate change to Hillary Clinton's emails, you can count on California's 77-year-old governor to have an opinion. Often, he's talking about new ideas he's taking on to address these issues in his own state, the most populous in the nation.
It takes a certain sort of person to rise the ranks in politics as Brown has — he was first elected governor in 1974 at age of 36 — then to climb them all over again. After serving two terms as governor, Brown took a break from the family business (his father was also governor of California) before serving as mayor of Oakland, then attorney general of California, then getting reelected to governor of California more than three decades from the last time, in 2010.
"I feel very vigorous," Brown told NBC's "Meet The Press" moderator Chuck Todd in an August interview, where he also compared Democratic front-runner Hillary Clinton's email controversy to a "vampire" and mused about the end of the world.
Brown has somehow managed to stay so current for so long that The Fix's Cillizza wrote in September there's even a case to be made he should run for president in 2016 (which would be his fourth attempt).
He left the option open earlier in the year, though a last-minute presidential bid by Brown seems highly unlikely at this point in the race.
Still, with a guy who's had as unbelievable a career as Brown has, you never know what to expect.
2. Maryland Gov. Larry Hogan (R)
One of the best feel-good political stories of the year comes from Maryland's new governor. Hogan, a Republican businessman running for office for the first time, achieved 2014's biggest upset when he won an open governor's seat in one of the most Democratic states in the nation.
But six months later, he announced he had an aggressive form of cancer, late stage 3 non-Hodgkin's lymphoma. Doctors had found 20 to 30 tumors all over his body, and the cancer was possibly entering stage 4. The prognosis didn't look good, but Hogan said he'd come out on top in fights with much tougher odds. "My odds of beating this are much, much better than my odds were at beating Anthony Brown," he joked of the sitting Democratic lieutenant governor he bested this past November.
Hogan kept up a public schedule as he underwent chemotherapy and no fewer than four spinal taps. A week before Thanksgiving, he held a press conference in front of family and friends to share some good news: He was cancer-free.
1. South Carolina Gov. Nikki Haley (R)
From her first foray onto the national stage when she won a crowded election to become South Carolina's first female and minority governor in 2010, the Republican Party has touted Haley as a rising star.
She had a rough first term, but Haley's star has arguably never shone brighter than this year. After an avowed white supremacist shot and killed nine black parishioners in a Charleston church this June, Haley handled her role as the state's griever-in-chief with grace, choking up in an emotional speech soon after, and a few months later delivering a speech in Washington calling on the GOP to be more tolerant toward minorities.
But it was the way Haley forcefully put herself at the front of the charge to end displays of the Confederate flag on public property that won her the most praise. As presidential candidates appeared to hem and haw, Haley called for the state legislature to remove the flag from statehouse grounds — something it did shortly after.
"I knew that it was giving a lot of people a pass to do what was right,” she told The Washington Post's Abby Phillip.
This year, Haley cemented her spot on the short list for the GOP nominee's vice presidential running mate.
Who'd we miss? The comments section awaits.