Measure 97 has shattered the state’s record for the most money contributed to a battle over a ballot measure.

The campaign to defeat the corporate sales tax measure has reached $22.5 million in contributions, more than double what proponents of the corporate sale tax have raised, according to campaign finance records. The Yes on 97 campaign has raised $10.9 million.

The record previously resided with the fight over GMO labeling in 2014, when opponents and proponents raised a combined $29 million.

In the past several days, three major grocery chains have contributed a combined $2.7 million in a final push against Measure 97, as voters received ballots in the mail this week. Costco, Albertsons/Safeway and Kroger/Fred Meyer each donated $900,000 to the campaign.

The Yes on 97 campaign also continued to receive donations, largely from public employee unions.

The measure would levy a 2.5 percent tax on the Oregon sales of “C” corporations exceeding $25 million, while “S” corporations — some with similar business structures and sales — would pay no additional tax.

Unlike S corporations, there are no limitations on the number of shareholders in a C corporation, and C corporations generally pay a corporate tax on the company’s income, while shareholders also have to pay taxes on any income or dividends they receive from the company.

The tax would yield about $3 billion per year in additional revenue for the state and provide a stable funding stream for state services such as education, health care and senior services. The tax targets mostly big corporations such as Costco and Walmart, but some homegrown Oregon businesses also would be affected.

However, the nonpartisan Legislative Revenue Office has estimated that the tax would likely cost the typical household about $600 more per year in the form of higher prices and slowed job growth.