If New Hampshire Democrat Maggie Hassan runs for Senate next year, she'll likely be the only sitting governor in the country to do so. There's little appeal for chief executives to trade their mansions and executive power to become just one of 100 in a deeply divided and partisan federal government.

But New Hampshire's uniquely powerless governorship makes the Senate look more attractive, and it's part of the reason why many Democrats and Republicans are already penciling Hassan in as Republican Sen. Kelly Ayotte's opponent in 2016.

The state's governors are historically weak, dating back to colonial times. Unlike most states' chief executives, they only serve two-year terms. What's more, there's an extra level above them on the New Hampshire government's organizational chart. A five-member executive council votes on every action Hassan and her predecessors have taken, from making government contracts to appointments—the sole purview of the governor in most other states. Almost no proposal from the governor can go forward without approval from a majority of the council, and right now, Republicans hold three of the five positions.

Not only are Democrats locked out of power in the state legislature after the 2014 elections, Hassan is in the minority in her own executive branch.

"As most councils tell governors, the first thing a governor has to do is learn to count to three," said former New Hampshire Gov. John Sununu, a Republican. "Every appointment the governor makes has to be approved by the council. … A lot of governors get frustrated with it."

"Our governor's office is one of the weaker governor's offices because the entire state government is designed to be weak," said Judd Gregg, another former Republican governor of New Hampshire who later ran for Senate (and previously served on the executive council).

Hassan's office brushed aside questions about a Senate run, insisting she "loves being governor" and plans to use her second term to "continue working with all Granite Staters" on "bipartisan solutions." But the conversation surrounding Hassan contrasts strongly with the handful of senators, like West Virginia's Joe Manchin, openly pining this year for the power of a governor's office, as well as Nevada Gov. Brian Sandoval's apparent resistance to Senate recruiting efforts in his state.

When current Democratic Sen. Jeanne Shaheen was governor, all five executive-council members were Republicans and they littered her path with roadblocks, according to Kathy Sullivan, a Democratic strategist and former state party chair. Plenty of Democratic governors have worked with Republican-held councils in the past, but the current council is particularly young and politically ambitious, which could complicate Hassan's state agenda.

"It was a position that a lot of folks took and stayed with for a long time," said Sununu. "But as is true of many offices now, people are running for them younger and being more mobile from one office to another, and so the council has been part of that shift."

Sununu's son, Republican councilor Chris Sununu, and Democrat Colin Van Ostern are both talked about as future governors. Democrat Chris Pappas is being encouraged to run for the 1st Congressional District. Meanwhile, another two conservative Republicans on the board will face potentially competitive reelection races in 2016. As they all calculate their political futures, decisions on the council will serve as a sort of voting record on potentially hot-button issues from Medicaid expansion to Planned Parenthood funding.

Meanwhile, Hassan would also have to run for reelection as governor in two years anyway. Vermont is the only other state with such short terms. And traditionally, governors haven't stuck around for more than three of those terms, though Hassan's popular predecessor John Lynch broke 100 years of state political convention by seeking a fourth. "You run for governor every two years and that can be a grueling part of the job, dealing with the politics," Sullivan said.

New Hampshire governors can do one thing on their own. Low-digit license plates—all the way down to a single number—are something of a status symbol in the state, and governors can distribute open numbers to the political elite and supporters to curry favor and praise local leaders.

"They're very coveted plates in the state," former Gov. Sununu said. "Historically, in New Hampshire, when someone gives up a low-digit plate and it's returned to the Department of Motor Vehicles, governors have been allowed to decide who might get that. … When we were putting on the 1988 Bush primary election campaign, I found out low-digit plates were wonderful tiebreakers when people were trying to decide between Bush and Dole and couldn't make up their minds."

For just about anything else, though, the governor's got to take it up the chain.