The party unity that held for Democrats during the government shutdown has splintered amid problems plaguing the federal online health insurance marketplace. And some Georgians are at the vanguard of the defection from the party line.

Rep. John Barrow of Augusta and Senate candidate Michelle Nunn are among the first Democrats to break ranks with their party over the timetable of President Barack Obama’s health-care overhaul. And their opponents are accusing them of flip-flopping in the name of their political livelihood.

The two Georgia politicians are among a growing number of Democrats seeking shifts both big and small to the health-care law. The state’s Democrats face a challenge trying to get a conservative electorate to embrace an initiative that’s become a favorite target of their Republican rivals.

Barrow became the first House Democrat this week to demand a delay of the requirement for individuals to purchase health insurance by March 31. He said taxpayers deserve the same protection that businesses received when the White House announced in July it would not penalize companies that do not provide health insurance until 2015.

“This isn’t about pointing fingers,” said Barrow, who faces a fierce re-election battle. “This is about providing some relief to the folks we represent who are facing serious uncertainty because they’re being forced to buy something that’s just not ready.”

Michelle Nunn, the Democratic front-runner for next year's open Senate seat, took a similar tack. She said she supported Republican Sen. Johnny Isakson's press for a one-year delay in the individual mandate, a proposal that's co-sponsored by Democratic Sen. Joe Manchin of West Virginia.

“It has become apparent in recent weeks that implementing this law will take some time. That’s why I supported a delay in the mandate on businesses,” she said in a statement. “And it is why, I believe that in light of the recent implementation challenges, I agree with bipartisan efforts led by Georgia Senator Johnny Isakson to postpone the insurance penalty for Georgia families.”

Republicans are pouncing on the shift. Former Secretary of State Karen Handel, one of five high-profile GOP candidates seeking the Senate seat, said Nunn was “already acting like a career politician.” And Rick Allen, who is seeking to unseat Barrow, said his opponent “owns this train wreck.”

Yet they have political cover from other Democrats. A group of 10 Democratic senators asked the White House on Friday to extend the open enrollment period for the health-care exchange beyond March 31 to avoid penalties for those who fail to sign up for insurance. The co-sponsors include several Democrats targeted by GOP candidates in conservative states.

Other high-profile Democratic leaders urge Obama to stay the course. Atlanta Mayor Kasim Reed, one of the state’s most influential Democrats, has trumpeted the law’s benefits across the city. At one City Hall event, he called the health-care law “transformational legislation,” and his spokesman Carlos Campos said Friday the mayor’s attitude hasn’t changed.

“He believes the Affordable Care Act needs to move forward and is confident the administration will work through these technical issues to help the uninsured get the coverage they need,” said Campos.