Business and conservative groups that spent tens of millions on advertising last year attacking health care reform bills in both chambers of Congress are mobilizing quickly to derail the latest efforts by the White House and Democratic leaders to pass a final measure this spring.

Employers for a Healthy Economy, a business coalition led by the U.S. Chamber of Commerce, is expected to launch millions of dollars worth of television and other media ads later this month and is now raising funds to do so. The business coalition spent an estimated $100 million last year on attack ads in conjunction with another chamber-led coalition.

"I have no doubt that the business community and others that are strongly opposed to the Senate and House versions of health care reform will go all out to stop the legislation," said Dirk Van Dongen, the president of the National Association of Wholesaler-Distributors which is one of about a dozen large members of Employers for a Healthy Economy.

Sources close to the chamber say that the coming ad drive will focus heavily on the House where a group of two to three dozen Blue Dog Democrats are viewed as pivotal votes. They're a prime target because the House passed its tough health care reform bill last year by only five votes; and the Democratic strategy now is to get the House to adopt the less ambitious health care bill passed by the Senate last year.

Separately, conservative groups that spent hefty sums last year against the same House and Senate bills have already begun to flex their muscles. For instance, the American Future Fund, an Iowa based conservative non-profit, spent about $500,000 on national cable TV and other ads in the week preceding the Feb. 25 White House health care summit, according to Nick Ryan, a spokesman for the fund.

"We'll certainly continue to be active," adds Ryan who points out that last year AFF spent close to $2 million on health care related ads and about $1 million on spots last month in Massachusetts to help Republican Scott Brown win his Senate seat. Ryan notes too that the fund's health care related ads last year were "focused on Blue Dogs" and that they will likely receive much more attention in coming weeks.

Americans for Tax Reform also expects to run more spots in the near future. ATR president Grover Norquist told National Journal that commercials are "likely" but said that a strategy was still being developed about targets in the House.

A foundation linked to Americans for Prosperity spent $250,000 on three days of cable TV ads in late February. The group has been raising money for weeks to launch a new commercial blitz which is expected to intensify this month. "They think that now is the time to go in [with ads] and try to establish the narrative," said one lobbyist.

And last week, the 60 Plus Association launched a $500,000 ad drive aimed at 18 moderate House Democrats who previously voted for the House bill last year but are now deemed on the fence about the legislation.

Some anti-abortion groups are also going to be weighing in. The Family Research Council, which poured $1 million into two TV commercials last year focused mostly on abortion, is expected to launch radio ads this month that will target about twenty to thirty House Democrats. "We're likely to run radio ads with a focus on the House and Democrats who oppose abortion," says Tom McClusky, the top lobbyist for FRC.

Last year, Rep. Bart Stupak, D-Mich., offered an amendment setting strict curbs on the funding of abortions under the final House health care bill that passed with the help of 64 Democratic votes. FRC and other conservative allies expect that many of these House Democrats will be upset with the softer curbs on abortions in the Senate bill, putting the lawmakers in play.