(CBS News) The Democratic Governors Association is upping the ante in Wisconsin, pouring another $1 million into the recall campaign against Republican Gov. Scott Walker.
The new investment -- given to the third party group Greater Wisconsin -- comes less than two weeks before the June 5 recall election. Polls show the controversial governor has a slight lead over his Democratic opponent, Milwaukee Mayor Tom Barrett.
The $1 million will help Greater Wisconsin air statewide ads and mobilize voters -- the Democrats' ability to turnout voters is expected to be a key factor in whether Barrett can overcome Walker's lead. The DGA has now spent more than $3 million in Wisconsin to bring down one of the nation's most contentious governors.
A poll released Wednesday by St. Norbert College and Wisconsin Public Radio showed Walker leading Barrett among likely voters, 50 percent to 45 percent -- within the poll's five-point margin of error. Other recent polls, including an internal Democratic poll and a poll commissioned by the libertarian Reason Magazine, also give Walker the lead.
The recall efforts against Walker were spurred by the controversial law he passed in the spring of 2011, nearly eliminating public workers' collective bargaining rights. The fight over the legislation prompted weeks of raucous protests in the state and inspired some Democratic lawmakers to flee the state.
The Wisconsin fight over union rights became the epicenter for a national debate over government priorities and Walker has been held up as a hero by the right and a villain by the left.
In a sign of the high interest in the race, the Milwaukee Journal Sentinel reports that 90,000 Wisconsin voters have already cast an absentee ballot. Even with election day still 12 days out, that figure exceeds the absentee voting in the primary earlier this month.
Updated to note that the libertarian Reason Magazine is not a partisan organization.