These men are careful to qualify their success. They have to be.

Republican Reps.-elect Frank Guinta and Charlie Bass will serve in the next Congress at the pleasure of New Hampshire voters ­— an electorate that embodies the sweeping shifts of recent cycles perhaps better than any other. It was just four years ago that Granite State voters ousted their two House Republicans and replaced them with Democrats. In 2010, both Democrats got the boot.

Bass was among the GOP faithful swept up in the anti-Republican wave in 2006. But he’s back, along with Guinta, who benefited from another wave that turned New Hampshire from blue to red seemingly overnight.

Granite State voters simply want balance in Washington, D.C., according to the state’s incoming Congressmen, who discussed their victories with Roll Call Friday morning.

Bass, a Congressman from 1995 through 2006, acknowledges a constant battle for New Hampshire’s famously fickle electorate: “The issue for 2008 and 2010 was about the independent vote. The independent vote in 2010 wanted change, and the Democrats were the incumbent party.”

“I think that New Hampshire people like split government. They don’t see it as gridlock. They see it as consensus building,” Bass told Roll Call in the Rayburn cafeteria shortly after Friday morning’s freshman class photo.

“The Republicans are sort of on probation now in the eyes of the voters,” Bass said. “We need to meet their expectations.”

“This is not a referendum on the good qualities of the Republican Party; it’s a referendum on the mistakes of Nancy Pelosi,” he added. “Mistake is a very mild term to use. She led her own party to ruin.”

Guinta, who joined Bass in last week’s new Member orientation, also sought to downplay historic Republican gains that flipped both state legislative chambers, with the GOP taking control of a combined 133 seats. (Voters did, however, re-elect Democratic Gov. John Lynch to a fourth term.)

“I would caution anyone who suggests it’s a mandate,” Guinta said Friday inside the Rayburn cafeteria, with maps of prospective offices splayed across the table in front of him. “I think it’s more about responsibility. People in New Hampshire who voted people in said, ‘There’s a job to do. That job needs to be done with civility and dignity. And then we’ll make a assessment two years from now.’”

Much has been written about the New Hampshire electorate joining the rest of New England in shifting left in recent cycles. But the truth is, the state continues to have an equal number of registered Republicans and Democrats — a sharp contrast from the rest of New England.

The secretary of state reports that roughly 29 percent of the electorate was registered with each party in May 2010. Far more voters ­— more than 42 percent — were unaffiliated.

New Hampshire voters, who flew “Don’t Tread on Me” Gadsden flags before it was tea-party trendy, have some things in common. They are largely white, make more money and are better educated than the national average, according to census data.

“New Hampshire voters are smart,” Guinta said. “Look, I’m one of them. We take it seriously. And I think we survey the challenges and make decisions based on whose willing to make tough, rational, reasonable and difficult decisions.”

Longtime pollster Andy Smith, director of the University of New Hampshire Survey Center, thinks the power of independents in the Granite State is exaggerated.

“It’s an absolute myth. But it’s such a good myth, it keeps getting repeated,” he said.

Smith’s research shows that most unaffiliated voters are really partisans; about 40 percent lean Democratic and 30 percent lean Republican. They also vote in much smaller numbers and pay less attention than the party-affiliated.

Smith said the results of recent wave elections are simply a matter of voter mobilization. Democrats had an 11-point voter turnout advantage in 2006, while unaffiliated voters narrowly broke for Democrats in that cycle.

It was far different this year, where Republicans had a 2-point turnout advantage and unaffiliated voters broke nearly 2-to-1 for Republicans, Smith said.

“It’s all about turnout,” he said, insisting the state is trending Democratic. “Democrats are moving here. And Republicans are moving to Florida or dying.”

Guinta and Bass acknowledge they may have challenging races in 2012 in the always-shifting Granite State. The White House has already reached out to both Democratic losers, Rep. Carol Shea-Porter and Anne McLane Kuster, encouraging them to run again.

Shea-Porter told Roll Call last week that she is considering another bid. And the New Hampshire Democratic Party said Kuster has already decided to run again.

The incoming Congressmen, however, said they have work to do before looking at re-election.

“I don’t care about being a Congressman. I’ve done that,” Bass said. “I ran because I think I can make a real contribution in a relatively short period of time to change America. And that’s going to be my focus. And if I keep that focus, I’m not going to have a problem getting elected next year. If people support what I’m doing, that’s what matters.”