Of course, the election was not between Obama and GOP candidate Mitt Romney, and analysts say it may have turned to a large degree on factors unique to Wisconsin and the recall battle, which Walker won with 53 percent of the vote to Barrett's 46.
For instance, 60 percent of voters in an exit poll said they did not think it was legitimate to recall a governor who had taken office little more than a year before and was not charged with official misconduct. In addition, Walker's push to strip most public employees of collective-bargaining rights - the very thing that sparked the recall campaign in the first place - was viewed positively by many Wisconsin voters who had seen property taxes go down in some localities because of lower costs for benefits and pensions.
But the Wisconsin outcome has to worry Democrats. It is a state that, until recently at least, has been a linchpin in the Obama strategy to reach the 270 electoral votes needed for victory. After all, no GOP presidential candidate has carried it since Ronald Reagan's 1984 reelection landslide. Obama won it by 14 percentage points in 2008.
That may have been misleading. Democrats John Kerry in 2004 and Al Gore in 2000 carried the state by less than a percentage point, and Republicans picked up two congressional seats and a Senate seat in the midterms in Wisconsin.
In addition, the recall fight offered a glimpse of life after the Supreme Court's Citizens United decision, which unleashed unlimited independent expenditures. Wisconsin showed Republicans' ability to marshal superior resources behind "super PACs" and other committees, money that trumped the Democrats' ground game. And the money spent in the Badger State was a mere appetizer: Conservative organizations have pledged to raise and spend $1 billion to defeat Obama.
The labor movement pushed for the recall, harnessing the anger stirred by Walker's moves against workers' rights. As he fought to keep his job, the governor became a hero to conservatives across the land and benefited from a wave of contributions from wealthy donors nationwide. He raised at least $30.5 million, to Barrett's $4 million.
On top of that, the Republican Governors Association and conservative groups such as Americans for Prosperity spent $16 million helping Walker, to roughly $14 million by labor and the Democratic National Committee.
Some of that money was brought to bear on Walker's behalf beginning late last year - he bought time in a Minneapolis TV market to saturate parts of western Wisconsin - while Democrats split their efforts in an intraparty primary battle. Barrett did not emerge as the nominee until March.
The state recall law gave Walker one more advantage: He could raise unlimited funds, just as super PACs can, while Barrett was limited to $10,000 per donation. "Money talks," said Sachin Chheda, a Democratic strategist who also is the volunteer chairman of the Milwaukee party. "That's the issue. Without that unequal spending, it could have been a different story."
Moreover, the exit poll showed Obama is still favored over Romney in Wisconsin by 51 percent to 44. The president also led on the question of who would be the best steward of the economy. Fully 18 percent of those who voted for Walker said they'd support Obama in November. Those numbers "demonstrate a very steep pathway for Mitt Romney to recover in the state," Obama's Wisconsin campaign director, Tripp Wellde, said in a statement.
But Ed Gillespie, a longtime GOP strategist and senior adviser to Romney, said the Wisconsin vote was a boost to the core Republican case in the presidential race for a smaller government. He said that the state may now become a battleground.
"I don't think we should assume . . . there will be a [Republican] victory in November in Wisconsin," Gillespie told reporters Wednesday at a Bloomberg News breakfast forum. "I do think it's in play, and that's telling."
In a memo about the results, RNC Chairman Reince Priebus, who is from Wisconsin, said the Obama campaign would now be forced to spend money and effort competing hard in Wisconsin. The campaign to save Walker also built a strong "infrastructure" for the GOP to use in the fall, he wrote.
Tuesday's results also were cited as evidence of labor's weakness, and seemed sure to embolden conservative governors elsewhere to move more aggressively against public employee unions. Foot soldiers in the smaller-government movement returned to their home states exultant.
"No politician was going to make difficult financial decisions if Walker got recalled," said Jennifer Stefano of Bucks County, director of the Pennsylvania chapter of Americans for Prosperity and one of many who traveled to Wisconsin to help mobilize conservatives there. "Now it's time to move."
Contact Thomas Fitzgerald
at 215-854-2718 or tfitzgerald@phillynews.com
or @tomfitzgerald on Twitter. Read his blog, "The Big Tent,"
at www.philly.com/bigtent.