WASHINGTON – As the White House prepares to launch a massive public education blitz aimed at promoting so-called Obamacare, President Barack Obama’s signature health-care reform legislation, congressional Republicans are waging relentless war against the law they’ve been bitterly attacking for almost four years.

More than 60 Republicans signed a letter Thursday urging John Boehner, speaker of the House of Representatives, to defund Obamacare when legislators vote to provide funds to the federal government before it runs out of money on Oct. 1.

“It is imperative, now more than ever, that Congress do everything in its power to halt the implementation of the health-care law,” Mark Meadows, a freshman congressman from North Carolina, wrote in the letter.

It’s yet another salvo in a protracted battle against Obamacare by Republicans, despite the U.S. Supreme Court’s ruling last year that upheld it as the law of the land.

Nonetheless, conservative legislators and their allies are mounting a counter-offensive against the Obama administration’s PR campaign, organizing town hall meetings, demonstrations and media blitzes of their own in the weeks to come as they urge uninsured Americans to refuse to obtain health-care coverage as required under Obamacare.

Sen. Marco Rubio, who’s quietly dropped his high-profile advocacy for immigration reform in favour of ginning up his fight against Obamacare, accused Obama on Thursday of failing to listen to the concerns of businesses about the costs associated with adhering to the law.

“Too often, politicians forget how their decisions impact real people,” he wrote in an opinion piece on FoxNews.com

“They dig in to protect their political agenda at all costs, even if it hurts the very people they were elected to serve … Instead of giving more speeches, I wish the president would listen more. He should listen to the people who took every penny they had saved and started their own businesses. They will tell him that Obamacare could force them to lay people off and maybe even close their doors.”

Obama is hitting back against Republican efforts to doom the legislation.

“There are folks out there who are actively working to make this law fail,” he said Wednesday, calling their attempts “a politically motivated misinformation campaign.”

The Affordable Care Act passed the House of Representatives, then under Democratic control, in 2009 with 220 votes, all but one of them Democrats. On Jan. 1, the federal government will begin subsidizing millions of Americans’ health insurance purchased through Obamacare.

In recent weeks, however, 251 members of the Republican-controlled House, including 22 Democrats, voted to postpone for one year implementation of one of the act’s key components — the mandate requiring big businesses to provide health coverage for employees, or face fines.

The White House agreed to the delay following complaints from business owners, who argued that the mandate was burdensome.

But Republicans have recently expanded their battle to include a push against the individual mandate, as well, arguing that private citizens are equally burdened by the requirement to buy coverage. They have portrayed the White House as bending to big business while ignoring the lowly individual who’s also required to buy coverage beginning Oct. 1.

House Republicans introduced a bill to delay the individual mandate as well “to make sure families and individuals get the same break from Obamacare that the president wants for big businesses,” said Boehner.

Twenty-two House Democrats voted for the bill, prompting Boehner to claim “bipartisan opposition to a partisan train wreck.” The bill, nonetheless, is destined to die in the Senate, which is controlled by Democrats.

Yet it’s full speed ahead anyway for Republicans, who view opposition to Obamacare as winning strategy with mid-term elections looming next fall. Usually only the most conservative members of the party’s base show up to cast ballots in the mid-terms, as opposed to presidential votes that draw a bigger, more moderate electorate.

Rubio is just one of many top-shelf Republicans who are urging Americans to stand their ground against Obamacare. Those same House Republicans have voted repeatedly to repeal Obamacare.

Sen. Mike Lee of Utah recently vowed to shut down the goverment entirely unless Obama defunds Obamacare. He’s backed in his move by two more moderate, and powerful, Republican senators — John Cornyn and John Thune.

Cornyn and Mitch McConnell, the Senate minority leader, even recently sent a warning shot to the National Football League, demanding in a letter that it cease co-operating with the Obama administration in its public-education campaign to tell gridiron fans about Obamacare’s benefits and how the law works.

“Given the divisiveness and persistent unpopularity of the health-care law, it is difficult to understand why an organization like yours would risk damaging its inclusive and apolitical brand by lending its name to its promotion,” the senators wrote.

Roger Goodell, the NFL commissioner, soon opted out of participating.

In response, Obama is now enlisting Hollywood for help in marketing enrollment for younger, uninsured Americans in health insurance exchanges, a key step in getting Obamacare up and running. If too few younger, healthier adults sign up for Obamacare, it will fail to extend coverage to millions of Americans at affordable rates.

Earlier this week, Obama met at the White House with Hollywood actors Jennifer Hudson, Amy Poehler, Michael Cera and Kal Penn. Also in attendance were representatives for Oprah Winfrey, Alicia Keys, Jon Bon Jovi, YouTube and Funny or Die, the comedy website founded by Will Ferrell.

The actors agreed to help, while Funny Or Die is reportely already working on Obamacare-related videos.

Conservative organizations, meantime, are also taking aim at young Americans.

FreedomWorks and Americans for Prosperity, a conservative group financed by billionaire industrialists David and Charles Koch, are targeting people in their 20s and 30s in their anti-Obamacare campaigns. FreedomWorks is in the midst of designing a symbolic Obamacare card that college students can set on fire during campus protests this fall.