The prospect of finally fixing America’s public schools looks better now than ever, but there’s still a chance that this golden economic and moral opportunity could slip away.

The danger lies in the possibility that Congress will delay action on education reform legislation and that a left-right coalition of reactionaries will consolidate next year to upend the dramatic progress now under way.

Polls indicate that education reform — including merit pay for teachers — is popular with the public, but teachers unions still resist it. The nation’s biggest civil rights groups do, too.

And now tea party-backed candidates around the country are calling for abolition of the Education Department, the driving force behind reform.

If Congress does not act this year to reauthorize the nation’s basic school funding law — and chances are, it won’t — and if Republicans take over one or both houses of Congress, the consensus for reform could collapse and funding for it could wither.

President Barack Obama is proving to be a courageous “education president.” He has hired an aggressive education secretary, Arne Duncan, and has promoted elevating education standards, accountability for teachers and reorganization of failing schools, even in the face of criticism from unions and civil rights groups.

Obama and Duncan have accelerated a reform process started by George W. Bush with his No Child Left Behind program.

The Democratic Congress approved $5 billion for Obama to award on a competitive basis to states undertaking reform. Eleven of them have won grants under Obama’s Race to the Top initiative, plus the District of Columbia, and 36 states instituted reforms to qualify for the competition.

Polls indicate broad bipartisan support for the elements of reform. ABC News found that 72 percent of parents support the idea of basing teacher pay on student achievement.

The latest survey by the journal Education Next and Harvard’s Program on Education Policy and Governance showed that 62 percent of adults support maintaining existing federal testing requirements and 58 percent support toughening education standards.

The survey found little difference between Republicans and Democrats on most phases of education reform — merit pay, tougher standards and charter schools — but wider gaps on the influence of teachers unions and increased spending on education.

Ironically, in view of an opposition blast in July from big civil rights groups including the NAACP, the National Urban League and the Rainbow PUSH Coalition, the survey showed that support for Obama’s reforms is much greater among African-Americans than in the general population.

For instance, 22 percent of the public regards Race to the Top as an “unnecessary intrusion” into state and local school management, while 32 percent consider it “necessary to improve” schools.

Among African-Americans, those numbers were 12 percent and 48 percent. Fifty-four percent of African-Americans support merit pay for teachers, and majorities even support vouchers and tax credits to enable children to attend private schools, which are beyond even the Obama agenda.

Meantime, by 46 percent to 22 percent, teachers think that Race to the Top is an “unwarranted intrusion” and 63 percent oppose merit pay.

The unions, the National Education Association and the American Federation of Teachers, seem to reflect their constituents’ attitudes. The civil rights groups plainly do not.

This summer, the NEA’s national convention passed a vote of “no confidence” in Obama’s program. NEA President Dennis Van Roekel said, “Today our members face the most anti-educator, anti-union, anti-student environment I have ever experienced.”

The AFT’s president, Randi Weingarten, has been more supportive publicly and has helped advance reform in the District of Columbia and New Haven. But he has fought other reform initiatives, such as expansion of charter schools.

Reform has been on the nation’s agenda since 1982, when the Reagan administration published the famous “Nation at Risk” report. Still, education performance has consistently dropped even as the importance of world-class schools has risen.

As Obama noted in a speech to the Urban League on July 29, the United States has fallen from first in the world in college graduation rates to 12th, and U.S. eighth-graders rank 10th on math and science tests.

Moreover, “African-American students not only trail almost every other developed nation abroad, but they badly trail their white classmates — an achievement gap that is widening the income gap between black and white, rich and poor.”

“This status quo,” Obama said, “is morally inexcusable” and “economically indefensible.”

The movement to advance education reform will get major boosts this fall with the national release of a documentary film, “Waiting for Superman,” by Davis Guggenheim, director of the Academy Award-winning film “An Inconvenient Truth.”

The movie tracks the heart-rending progress of parents and children participating in a lottery to gain admission to quality charter schools — with a loss leading to placement in an inferior public school and, likely, academic failure.

The movie excoriates the influence of teachers unions in defending incompetent teachers.

In addition, NBC is devoting time on all of its owned networks to promote reform in a series called “Education Nation.”

And America’s Promise Alliance, the youth group founded by former Secretary of State Colin Powell, is mobilizing 400 national business, government and nonprofit groups in a program called Grad Nation, designed to reverse the nation’s high school dropout rate — 30 percent for all students, 50 percent for minorities.

All this is to the good. The danger is that Congress will fail to pass a reauthorization of the Elementary and Secondary Education Act, locking school reform into law, or extend funding so that Race to the Top can continue.

If Republicans capture control of one or both houses of Congress, ESEA reauthorization will be further delayed — especially with tea party activists demanding local control of education — and education funding might well be cut amid a general hold-down on domestic spending.

Moreover, one of the nation’s leading experiments in reform may come to a halt if District of Columbia Mayor Adrian Fenty is defeated in a primary election this month. His opponent, Vincent Gray, has refused to say whether he will retain D.C.’s reformist schools chief, Michelle Rhee.

America can’t afford to have its schools less than world class, and a majority of Americans seem to know it. But reform has failed before and could again.