Shrugging off millions of dollars spent by labor groups to defeat him, Tom Barrett strolled to victory in Tuesday's Democratic primary and set up a more taxing sprint toward June 5 - a historic recall that will be a rematch of his unsuccessful 2010 race against Gov. Scott Walker.

In the recall primary, the Milwaukee mayor easily defeated former Dane County Executive Kathleen Falk, showing that more than $4 million from outside groups doesn't necessarily buy a close race.

As Barrett was campaigning Tuesday, Walker was barnstorming the state and showing the fight he will bring to what is expected to be a brutal month of canvassing for one of the most important elections to state office in Wisconsin history. A poll last week showed Walker and Barrett in a dead heat.

Walker, who won over 600,000 votes despite facing only token opposition Tuesday, has been preparing for months for the fast-approaching election, raising a record $25 mil lion, while Barrett must now pivot toward this race with far fewer resources.

Addressing jubilant supporters at the Hyatt Regency in downtown Milwaukee, a fiery Barrett called for unifying his party and ending Walker's term before it reaches a year and a half. Barrett, who defied unions by getting in the race, repeatedly referred to himself as the independent candidate in his speech to supporters and said he would not be beholden to special interests .

"Do we want a governor who has divided this state like it has never been divided before? Do we want a governor who has caused this state to lose more jobs than any other state in this country?" Barrett asked the crowd. "This race is not about the past. It is not about the past. It is about the future of Wisconsin."

Also Tuesday, Madison firefighter and union leader Mahlon Mitchell easily advanced to the general election for lieutenant governor by defeating private investigator Ira Robins and fake Democrat Isaac Weix in the Democratic primary. That sets up a recall election next month against GOP incumbent Rebecca Kleefisch, who did not have a primary.

Walker won his own race, crushing the liberal spoiler candidate Arthur Kohl-Riggs, who ran as a Republican. Speaking to a crowd of fired-up supporters at the GOP office in Waukesha, Walker called on voters to reject the recall and give him the rest of his four-year term.

"Do we want to go back to the days when a handful of special interests controlled our state and local governments? No. Instead, we put in place reforms that rightfully put the hardworking taxpayers of Wisconsin in charge. We're not going backwards. We're going forward," Walker said.

The Democrats barely drew more votes Tuesday than Walker, in spite of the fact that their party had a competitive primary and Walker did not.

With 95% of the vote counted, Walker had nearly as many votes as all the Democrats combined in their primary.

Barrett and Falk are slated to appear at a unity event together at 11:15 a.m. Wednesday at Barrett's house along with the other two Democrats in the primary, Secretary of State Doug La Follette and state Sen. Kathleen Vinehout of Alma. Unions will be holding their own rally at the Capitol as well.

Falk concedes

At the Edgewater Hotel in Madison, Falk supporters cheered wildly and waved green and white Falk campaign signs as she conceded defeat to Barrett.

"Tom Barrett will focus on the real needs of our state, jobs and education. Just as you supported me, we must now support him," Falk told her supporters, pledging that in June Democrats will "get our state back."

It was Falk's third loss in a statewide race, and the second time she did not advance beyond the Democratic primary. With 78% of precincts reporting, she was losing 2-1 in Dane County, where she served as county executive for 14 years. She was losing 3-1 in Barrett's home turf of Milwaukee County.

In a recall campaign that is a do-over of the November 2010 election, Barrett faces an obvious challenge - Walker beat him by nearly 6 percentage points in November 2010.

This time, Walker has used the state's recall law to raise unlimited donations as large as $500,000 from single donors and still had $4.9 million in the bank as of April 23. Barrett, by contrast, had to stick to the usual limits and raised $831,500 through that date and had $475,500 on hand heading into the general election.

Unprecedented fundraising by Walker and heavy spending by independent groups backed by corporations and unions have already pushed the total amounts spent and raised to an estimated $42 million. That already tops the estimated $37.4 million spent by candidates and independent groups in the 2010 governor's race.

Highlighting the shift to the general election, the liberal Greater Wisconsin Political Fund also launched a new attack ad Tuesday about the secret John Doe investigation into Walker's aides during the time he served as Milwaukee County executive.

The effort to recall Walker was prompted by his successful plan to curb collective bargaining for public employees and the massive protests that ensued, but the campaign itself appears likely to center on the economy, just as the 2010 race did. Wisconsin lost more jobs last year than any other state, and Barrett has contrasted that with Walker's 2010 promise to create 250,000 jobs during a four-year term. Walker has countered that he should be given a shot to let his policies work and that Milwaukee's economy is among the worst in the country for large cities.

Mordecai Lee, a professor of governmental affairs at the University of Wisconsin-Milwaukee, said the general recall election will rank among those that decided the fates of legendary state figures like U.S. Sens. Bob La Follette and Joe McCarthy. Some outside Wisconsin have ranked it as one of the most important elections in the country this year after the presidential contest.

"In a handful of political events in Wisconsin's history, this is on one hand," said Lee, a former Democratic state senator. "This is just an unbelievably important moment."

Mark Graul, a strategist who has run statewide campaigns for Republicans, said that he expected a tight general election that would be driven less by persuading undecided voters and more by turning out voters who are already decided. He said that the results of the election could help decide whether recalls become a more common occurrence in state politics.

"It's obviously a historic election. It's only the third one (for governor) in the nation's history. It's got some very real ramifications on state policy," Graul said.

Larry Sabato, director of the Center for Politics at the University of Virginia, said that he gave an edge to Walker for now, in part because some voters see recalls as a "drastic process."

"I think people have a hesitation about ousting their governor in midterm," Sabato said.

But Walker faces challenges of his own. Though he has more money to run campaign ads, most people have already decided whether they support him, leaving few undecided voters to influence with his funds.

History also gives Walker reason for caution. As Graul noted, he is just the third governor in the country's history to face a recall. California Gov. Gray Davis in 2003 and North Dakota Gov. Lynn Frazier in 1921 both lost.

Barrett showed Tuesday he could overcome determined opposition from some within his own party.

Falk had a head start of two and a half months over Barrett, who had to manage his April re-election race for mayor at the same time he prepared for the recall race. She won the backing of major state labor groups such as the Wisconsin AFL-CIO, the Wisconsin Education Association Council and the American Federation of State, County and Municipal Employees, as well as environmental groups such as the Sierra Club.

With money from public employee unions, the outside group Wisconsin for Falk spent more than $4 million on television ads and mailers touting Falk, who pledged to veto any budget that does not restore the collective bargaining for public employees that Walker repealed last year.

On top of that, Republicans overwhelmingly focused their attack ads on Barrett, signaling that they saw him as the stronger candidate. Polls backed that theory, with Barrett performing better than the other Democrats in head-to-head matchups against Walker.

But Barrett overcame that opposition from both unions and Republicans.

Barrett is well known from his 2010 run for governor, his time as mayor and his stints in Congress and the Legislature. He appeared to appeal to more moderate voters, especially after Falk made her veto pledge. Barrett said he would take a less confrontational approach by calling a special legislative session on the issue.

With help from the independent ads, Falk overcame much of the gap in name recognition with Barrett, but the veto pledge drew criticism from other Democratic candidates and polled poorly even among Democrats.

While the Democratic primary was crowded, the race stayed largely positive, with few direct attacks coming from either candidates or outside groups. It was the second time Barrett and Falk faced each other in a primary for governor. Both ran in 2002, with Barrett coming in second and Falk third behind then-Attorney General Jim Doyle.

Despite their earlier opposition, Barrett immediately won statements of support from unions that had backed Falk. The Wisconsin Education Association Council and the American Federation of State, County and Municipal Employees - whose leaders tried to keep Barrett out of the race - issued statements saying they were supporting him.

A poll released last week by Marquette University Law School showed Walker and Barrett statistically tied. Barrett led Walker 47% to 46% among registered voters; Walker led Barrett 48% to 47% among likely voters.

Conducting the primary was expected to cost about $9 million. The general recall election is projected to cost the same, according to the Government Accountability Board, which runs state elections.

GOP officials fielded protest candidates like Gladys Huber in the Democratic gubernatorial primary and Weix in all recall races around the state to ensure that they would all be decided at the same time on June 5.

Milwaukee Journal Sentinel reporters Bill Glauber contributed to this article from Milwaukee, Mike Johnson from Waukesha and Meg Jones from Madison.