Super PACs and labor groups have combined to spend over $13 million in the Massachusetts governor’s race to date. Outside groups have outspent the gubernatorial field — the two major gubernatorial finalists, their running mates and political parties — by $1.5 million this year. The $13 million in outside PAC and labor money represents a new high-water mark for outside spending in a Massachusetts governor’s race, and it’s helping tilt the campaign in Charlie Baker’s direction.

A pair of 2010 Supreme Court rulings enabled wealthy individuals, outside political action committees and labor groups to bypass certain campaign finance restrictions and spend unlimited amounts of money on political races, as long as the outside groups don’t coordinate political strategy with the candidates they support. The groups the Supreme Court created, super PACs, have reset the balance of power in campaigns across the country.

Outside PACs and labor groups spent heavily in the 2010 gubernatorial contest between Gov. Deval Patrick and Charlie Baker. The Republican Governors Association spent $4.7 million on television ads attacking Patrick and an independent candidate, Tim Cahill, while a pair of Democratic-aligned groups spent $6.3 million beating up on Baker on television. One of the groups spending on Patrick’s behalf, the Massachusetts Teachers Association, outspent Baker in the final weeks of the race.

For every $10 spent by Patrick and Baker, their running mates, and state political parties in 2010, super PACs and outside labor groups spent $6. And the outside groups have only grown in stature and sophistication since the 2010 race.

Super PACs and labor groups passed their 2010 spending mark last week. Their combined spending total now stands at $13.3 million. With less than two weeks until Election Day, the pace of outside spending is accelerating. A PAC supporting Baker’s candidacy spent $2.25 million early this week. Millions more are waiting on the sidelines.

Super PAC Spending Hits Record Levels

The Republican Governors Association has been the heaviest spender, by far, in the race between Baker and Coakley. The RGA has spent $8.3 million on Baker through a pair of super PACs: Commonwealth Future, a PAC that has dominated television airwaves, and the American Comeback Committee, a committee devoted to direct mail.

Commonwealth Future has roughly $1.4 million sitting in its coffers for a final advertising blitz, meaning that by Election Day, the RGA will have doubled its Massachusetts spending from 2010.

Heavy Republican super PAC spending has turned the tables on Massachusetts Democrats, who enjoyed a significant edge in outside spending four years ago. This year, Democrats’ primary vehicle for outside spending is the Mass. Independent Expenditure PAC, a committee funded by the Democratic Governors Association, EMILY’s List, and several labor unions. The Democratic PAC has spent $3.6 million on ads attacking Baker, while the Service Employees International Union has spent $400,000 paying canvassers to knock doors for Coakley.

All told, Democratic outside groups have been outspent by Republicans by more than two-to-one. (That calculation does not include the $750,000 outside individuals spent on Steve Grossman’s Democratic primary bid.)

The $4 million Republican edge in outside spending is exacerbating an already serious Democratic money gap. Baker, his running mate Karyn Polito, and the Republican State Committee have a $2 million overall spending edge over Coakley, her running mate, and the Democratic State Committee. Baker and the Republicans have outspent Coakley and the Democrats by $2.3 million since September 1. Republicans’ super PAC spending edge pushes the overall spending gap over $6 million.

Four years ago, Baker’s campaign outspent Patrick’s, but a Democratic edge in outside money evened the spending race between the two camps. This time around, outside money is turning an already lopsided money race into a rout.

This story was cross-posted to Poll Vault, a data-driven look at the 2014 election produced by WBUR, The MassINC Polling Group, and CommonWealth.