By Hillary Borrud

The costs of Oregon's most contentious campaigns continue to rise in the final days before the election.

As of Friday, supporters and opponents of the corporate gross receipts tax Measure 97 reported nearly $42.3 million in combined spending, according to analysis of campaign finance data from the Oregon Secretary of State's office. That far exceeds the previous record for the costliest Oregon campaign, which was set in 2014 when opponents of a measure to label genetically modified foods spent nearly $21 million and supporters spent $8 million. Spending by candidates for governor and secretary of state also reached into the millions.

Those tallies will rise after Election Day, as campaigns report the cash that continued to trickle -- or pour -- into their coffers in the last days. Under Oregon law, campaigns have up to seven days after receiving money to report it to the Secretary of State's office.

'Yes' on Measure 97 campaign

As of Friday, supporters of Measure 97 had reported raising $16.4 million and spending $12.8 million through three associated political action committees.

Largest campaign donors:

1: Service Employees International Union, $5.1 million

2: Oregon Education Association, $4.4 million

3: National Education Association, $2.3 million

4: American Federation of Teachers, $1.8 million

5: American Federation of State, County and Municipal Employees, $1.6 million

These totals combine contributions since 2015 to the political action committees Yes on 97, A Better Oregon and Defend Oregon, all of which are working to pass the corporate tax measure.

Defend Oregon focused solely on passing Measure 97 until recently, when the group updated its state registration to reflect that it now supports seven of the 15 statewide measures on the November ballot.

'No' on Measure 97 campaign

As of Friday, the campaign to defeat Measure 97 had reported raising $25.9 million and spending $23.6 million.

Largest campaign donors:

1: Albertsons-Safety, $2.1 million

2: Costco, $2.1 million

3: Fred Meyer's parent company Kroger, $2.1 million

4: Lithia Motors, $905,000

5: Cambia Health Solutions, $550,000

Opponents of Measure 97 so far appear to have only one political action committee, Defeat the Tax on Oregon Sales.

(c)2016 The Oregonian (Portland, Ore.)