Milwaukee Mayor Tom Barrett (D) was the top beneficiary of outside spending in the Wisconsin recall battle in the past month, with Democratic groups stepping up their contributions after the May 8 Democratic primary.

According to an analysis by the Campaign Media Analysis Group for WisPolitics.com, outside groups spent $3,487,144 on behalf of Barrett and $2,333,130 on behalf of Wisconsin Gov. Scott Walker (R), whom the mayor is hoping to unseat in the June 5 recall election.

The biggest spender in the two-week period starting May 10 was the Republican Governors Association's Right Direction Wisconsin PAC, which paid out $2.3 million in pro-Walker work. On the Democratic side, the Greater Wisconsin Political Independent Expenditure Fund spent $1.8 million to help Barrett, followed by the We Are Wisconsin Political Fund at $1.5 million.

The totals do not include so-called "issue ads" run by outside groups that criticize or praise a candidate's positions. For example, the Wisconsin Manufacturers & Commerce spent another $713,070 on broadcast TV alone for ads praising Walker in the two-week period starting May 10.

Third-party groups also poured money into the four state Senate recall races, with Democratic candidate John Lehman getting the most. From the WisPolitics.com totals:

- $737,162 to support Dem Senate candidate John Lehman

- $365,761 to support Dem Senate candidate Kristen Dexter

- $269,443 to support GOP Sen. Terry Moulton

- $68,658 to support GOP Sen. Van Wanggaard

- $23,132 to support Dem Senate candidate Donna Petrowski

- $21,132 to support Dem lt. guv candidate Mahlon Mitchell

- $14,428 to support GOP Senate candidate Jerry Petrowski

A list of all the expenditures by outside groups since the May 8 primary can be found here.

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