A TV ad war is raging on healthcare legislation. And it’s costing millions of dollars on both sides. USA-HEALTHCARE/OBAMA

The campaign-style messages target Democratic and Republican lawmakers who will decide the fate of the White House-backed measure, and are up for reelection in November.

“Pass health insurance reform now,” declared an ad by Health Care for America Now, a coalition of more than 1,100 groups — including labor, civil rights, children and women. The group announced it had begun airing the spot on Tuesday in selected congressional districts at a cost of $1.4 million.

Also on Tuesday, the House Republican campaign committee announced it had prepared TV ads to run against dozens of wavering House Democrats. The committee said any Democrat who ends up voting yes can expect to be hit quick and hard by a TV ad blitz in their congressional district.

A group of businesses headed by the U.S. Chamber of Commerce¬† is also airing TV ads against the legislation, spending between $4 million and $10 million, according to a spokeswoman. While Moveon.org, a liberal advocacy group that helped Barack Obama win the presidency in 2008, is running ads in support of the measure, spending “in six figures,” an official of the group said.