SALEM — While business groups look like they will be successful in sending to the voters a measure that could overturn the Oregon Legislature’s $733 million tax hike on corporations and high-income earners, two other anti-tax referendum campaigns are struggling.

There’s been a greater push by business groups to try to undo the $733 million tax hike than to block tax increases that would fund an expansion of health coverage to an additional 80,000 uninsured children and 35,000 low-income adults, and to pay for road improvement projects.

“It’s clear the business interests didn’t want to run against providing health care for little kids or creating better roads. What they want to run against is big government getting bigger,” said Jim Moore, a political science teacher at Pacific University in Forest Grove.

The Democratic-led Legislature approved the income tax increases, saying the money is needed to balance the budget and to protect schools and safety net programs for needy Oregonians. They also said the higher taxes are aimed at those who can most easily afford to pay them.

The deadline for gathering signatures for the tax referendum campaigns is Friday, Sept. 25.

The campaign group that’s seeking to kill the tax hikes on corporations and high-income earners, called Oregonians Against Job-Killing Taxes, already has raised more than $1 million from business organizations, timber companies and others.

If the tax opponents round up enough signatures — as expected — the tax package will be submitted to a statewide vote in a special election Jan. 26.

The tax hike package, which has drawn staunch opposition from most of Oregon’s major business organizations, would raise corporate taxes and increase income taxes on individuals with a taxable income of more than $125,000 a year or households making above $250,000.

Business groups backing the referendum effort argue the tax increases will slow Oregon’s economic recovery and cause more job losses.

“We recognized early on that we needed to focus our time and resources on the two taxes that we think will harm our economy the most,” said anti-tax activist Russ Walker, who’s part of that effort.

But there has been far less financial support from the business community for campaigns against tax hikes to expand state health coverage and to pay for road improvement projects.

In addition, those two campaigns got off to late starts.

Grants Pass attorney Jack Swift, one of the co-sponsors of the effort to overturn the health plan, said voters ought to be given a chance to weigh in on the combination of taxes on hospitals and insurers.

However, with no financial backing and less than six seeks to gather at least 55,179 valid petition signatures, the purely volunteer effort is having a tough time, he said.

“Did we know it was going to be difficult, an uphill climb? Absolutely,” Swift said.

The legislation that Swift is fighting would impose a 1 percent tax on health insurance premiums, and would also allow insurers to pass on the tax to employers and policyholders.

The expansion of health care to an additional 80,000 children in Oregon would be the biggest passed by a state legislature this year — Montana comes in second at 30,000 — and puts Oregon on track to covering nearly every child. Oregon is one of 12 states with universal health care for children.

The other bill being fought by anti-tax activists would fund a $300 million-a-year transportation package with a 6-cent-a-gallon gasoline tax increase as well as higher fees on motorists.

Veteran anti-tax activist Don McIntire is co-sponsoring the effort to derail the road improvement package.

His group, Oregonians Against Highway Robbery, has gotten about $30,000 in contributions and is relying mainly on volunteers to gather the needed 55,000 signatures by the deadline next Friday.

McIntire won’t speculate about whether his group will be able to round up enough signatures.

“We are working as hard as we can,” he said. “But it’s a huge job. We had a late start and there’s no big money behind us.”

Walker, who is part of the effort to overturn new taxes on corporations and high-income earners, said he hasn’t detected much petition circulating activity by either the gas tax or health care referendum campaigns.

Those two campaigns haven’t generated much momentum because business groups have had mixed views on those issues throughout the year, he said.

“I don’t think either one of them will make the ballot,” said Walker, who is the Oregon director of the national fiscal conservative group FreedomWorks.