Indiana has become the first of 45 states to opt out of the national education standard known as Common Core, and critics of the controversial K-12 program say the move could "open the floodgates" for others to follow.

Growing criticism over costs imposed by the program, as well as fears that by setting a national education standard, the program has already begun dictating curriculum, has made Common Core an increasingly polarizing issue. Although the program has both Republican and Democrat supporters, Indiana Gov. Mike Pence predicted his state will be the first of many to rethink participation.

"I believe when we reach the end of this process there are going to be many other states around the country that will take a hard look at the way Indiana has taken a step back, designed our own standards and done it in a way where we drew on educators, we drew on citizens, we drew on parents and developed standards that meet the needs of our people," Pence said.

The Common Core State Standards Initiative, originally drafted by state education superintendents working with the National Governors Association, and since embraced by the Obama administration, seeks to impose a national standard for achievement among K-12 students. Some states began implementation this year, with the majority slated to begin in the fall.

But several states are seeing a backlash against participation, which was typically approved as long as five years ago. Jim Stergios, executive director of the nonpartisan, Boston-based think tank Pioneer Institute, said the Hoosier State's move could "open the floodgates."

"Indiana, under [Republican Gov.] Mitch Daniels, was one of the early proponents of Common Core, even the poster child," Stergios told FoxNews.com. "By pulling out, it sends a strong signal to other states, particularly red states, that, 'Hey, if they can do this, then why can't we?'"

Common Core officials said in a statement the decision was Indiana's to make, and pledged to work with the state in whatever way was possible.

"States have always been in full control of determining which standards are right for their students," Carissa Miller, deputy executive director for the Council of Chief State School Officers, said in a statement. "CCSSO has stated from the beginning of this effort that we support states in choosing higher, clearer standards that prepare students for college and career and that the Common Core was one path. We look forward to continuing to support Indiana with their college and career-ready standards.”

Although Common Core has been in the works for years, Stergios said it is not surprising that the real opposition has galvanized now that it has begun to influence curriculum and have an impact on state and local budgets. FoxNews.com reported last month that states face unfunded mandates totalling $10 billion or more, as well as annual cost increases to comply with the programs testing component.

"The whole process behind Common Core was developed in a way to minimize input or popular knowledge of what was going on," Stergios said. "It was to be expected that parents would not react, positively, or negatively, until their kids started coming home with this new material. And legislators only start to get the message when they are confronted by new costs and angry voters."

A handful of other states have opted out of the assessment component of Common Core, though they presumably will mandate that districts comply with curriculum that prepares students for the standards. Other states, including Arizona, have renamed the program with their states, hoping to avoid the polarizing title while still implementing the program.

"We have yet to see leadership like that shown by Gov. Pence in any other state," said Glyn Wright, executive director of the Eagle Forum, a think tank that has also been highly critical of Common Core. "We hope that other principled governors like Scott Walker (Wisconsin), Bobby Jindal (Louisiana), and Sam Brownback (Kansas)will emulate Governor Pence’s leadership by defending taxpayers, families, and state sovereignty in leading their state out of the Common Core."

Critics say Indiana is also simply stripping the "Common Core" label while largely keeping the same standards in place. This year, the Republican-controlled Legislature approved a measure requiring the State Board of Education to draft new benchmarks for students.

The draft for those standards, put out for review last month, has already drawn skepticism from Common Core critics, including an analyst hired by Pence to assess the new program. That analyst, retired University of Arkansas professor Sandra Stotsky, says the proposal is just too similar to Common Core.

Stotsky released an internal Indiana Department of Education report that found that more than 70 percent of the standards for sixth through 12th grade are directly from Common Core, and about 20 percent are edited versions of the national standards. About 34 percent of English standards for kindergarten through fifth grade were taken straight from the national standards, and an additional 13 percent were edited.

Stotsky called the proposal a "grand deception." The State Board of Education is scheduled to vote on it on April 28.

"It makes a fool of the governor," Stotsky said. "The governor is being embarrassed by his own Department of Education if the final version is too close to Common Core."

Oklahoma is among states considering implementing different standards. A state Senate panel voted Monday in favor of a measure that would effectively halt the use of Common Core.

The Common Core replaced a patchwork of varying standards from state to state, and supporters say it gives both consistency and academic rigor. Advocates say it is needed in order to guarantee a baseline of learning, so students from every state will share certain educational standards. They also insist that the program does not commandeer curriculum decisions, though critics say curriculum companies are churning out new "common core -aligned" lesson plans that reflect the standards.

The Associated Press contributed to this report