Machado alleges that in 2006, Silva took "a series of retaliatory and discriminatory actions" after it became clear that she planned to challenge Silva for the presidency. Machado claims she was demoted without warning and given impractical assignments in the existing administrative position she held.
"In short," the suit alleges, "Silva made it impossible for the plaintiff to complete her job and campaign effectively."
After Machado lost the election, she claimed the "voting process appeared suspicious" and appealed to a union board. The board split its vote about whether the election should be overturned, handing the election to Silva, the suit says.
The next day, June 30, 2006, Machado was fired and denied two weeks of pay. Machado filed suit, and in a partial settlement won back her severance.
These allegations were included in a second suit that Machado filed in February against her attorney, whom she accused of failing to pursue her claims of discrimination and retaliation. But the conflict also crops up in two rulings from the National Labor Relations Board, in which employees of a nursing home, apparently siding with Machado, sought to have Silva replaced as a contract negotiator.
Machado could not be reached for comment.
Silva said she was not familiar with the lawsuits. She described Machado as a "disgruntled employee."
"I won't comment on what was an internal personnel issue between the union and a former employee," she said.
Silva described the contentious election as part of a "democratic process," and said, "It's not unusual for this kind of situation to occur.
"Whenever you have an election, you are going to have winners and you are going to have losers, and sometimes the losers don't go away quietly," she said.
The crux of her job representing mostly nursing-home workers, she said, provides crucial experience for government. She has sought to raise wages, protect workers, and work cooperatively with management, she said, and making those deals doesn't always make everyone happy.
"My approach is, we have to figure out what the win-win is here," she said. "I'm going to be fair, and I'm also going to be tough."
At a campaign event Tuesday in Willingboro, the day after Buono announced Silva as her running mate, Buono was asked about the lack-of-experience charge from the Christie campaign. She pointed to Arnold Schwarzenegger and Ronald Reagan, who became California governors without prior political experience. (Reagan also had been a union leader.)
"Somehow they're qualified, but a woman who has the vast experience that Milly does in bringing people together, in forging compromises and moving the state ahead in terms of working people in New Jersey, why is that singled out as not being enough?" Buono asked.
Silva would be the first sitting labor leader to win a statewide office in decades, historians said.
As lieutenant governor, Silva would step in as governor if Buono were incapacitated. She could also have additional duties - Christie's lieutenant governor, Kim Guadagno, doubles as secretary of state in charge of elections - but Silva said she and Buono had yet to discuss those possibilities.
The other major criticism that Silva has faced so far from the Christie camp - and from the governor himself - is her failure to vote in the 2009 gubernatorial election (in addition to elections in 2007 and 2011). On Tuesday, she attributed her work across the state in mobilizing union members to get out the vote as the reason she could not get to the polls.
Buono and Silva are only the third all-female gubernatorial ticket in American history, and gender has proved to be a factor in the campaign. Both are mothers who struggled financially early in life, and they have focused on Christie's cuts to women's health clinics.
On Wednesday, their campaign highlighted a slight from Hudson County Republican Chairman Jose Arango, who in an interview with PolitickerNJ.com dismissed Silva as an inexperienced "secretary." The Buono campaign and female Democratic legislators demanded that Christie call for his resignation.
This month, before she was named to the ticket, Silva referred to the gender issue on Twitter, writing that Buono was "standing up for NJ despite party-boss structure keeping women down."
Asked whether male Democratic Party bosses in New Jersey - who have had warmer relations with Christie than Buono - were intentionally keeping Buono down, Silva said she thought the Democratic Party was "coming together."
"Whatever issues that might have existed in terms of process . . . they are united now," she said, "and they understand that what we need to do is elect Barbara Buono."
Contact Matt Katz at 609-217- 8355 or email@example.com, or follow on Twitter @mattkatz00. Read his blog, "Christie Chronicles," at www.inquirer.com/christiechronicles.