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TALLAHASSEE (CBSMiami/NSF) – In her 23 years in Congress, Jacksonville Democrat Corrine Brown has faced challenges before, from highly touted Republican recruits to questions about her ethics. But she has emerged time and again, winning 12 elections — almost all of them blowouts.

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And in Washington, Brown pushes to fulfill her campaign slogan — “Corrine Delivers” — by bringing home spending for a district that has more than its share of low-income neighborhoods.

Now, though, Brown is facing a pair of challenges that have combined to make the Aug. 30 Democratic primary in the 5th Congressional District the biggest test yet of her staying power.

On Friday, Brown appeared in a federal courthouse in Jacksonville, where she pleaded not guilty to 22 criminal counts including conspiracy, mail and wire fraud and violations of tax laws. Federal prosecutors say Brown, 69, and her chief of staff Elias “Ronnie” Simmons worked with Carla Wiley, a Virginia woman who reached a plea deal with the government in March, to set up a sham charity used mostly to pay for personal expenses.

At the same time, the new reshaping of Brown’s district under the state’s voter-approved ban on political gerrymandering means the longtime congresswoman will face thousands of voters who have never seen her name on a ballot.

“I think the one reason why she’s at risk this cycle is because the district has changed,” said Steve Schale, a Democratic strategist.

Brown’s stronghold in Congress was oriented north-south, most recently winding its way from Jacksonville to Orlando. But the courts struck down that district, saying it was intended to help Republicans by removing black voters from the surrounding districts.

Over the congresswoman’s heated objections — she once compared the redrawing of the lines to slavery — the district now runs from Jacksonville in the east to Gadsden County in the west, cutting through Tallahassee along the way.

That has prompted former state Sen. Al Lawson, a Democratic fixture from the Tallahassee area who has unsuccessfully run for Congress twice, to challenge Brown for the seat. LaShonda Holloway, a former congressional staffer, is also running in the race.

So far, Lawson has only termed the charges “unfortunate,” but Brown has come out swinging against the allegations. While she said Friday that she would “let the work I’ve done speak for me,” one of her lawyers lambasted the federal government for the way it conducted the investigation. Attorney Betsy White also made what could almost have been a campaign speech for Brown.

“It is ironic that we are speaking in front of the Bryan Simpson Federal Courthouse, for which Congresswoman Brown was instrumental in securing funding for,” White said. “The construction of this very courthouse is but one of the many, many projects which have been completed in this community because of the efforts of the congresswoman.”

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In a blog post over the weekend, Brown suggested that race played a factor in the charges against her, while also trying to remind voters of what she’s done for them.

“Yet my conscience is clear because I’m innocent. I’m not the first black elected official to be persecuted and, sad to say, I won’t be the last. … Despite all the heartache my family and I have experienced, I want you to know that I’m still in the fight to provide the representation you deserve in Washington,” Brown wrote.

For now, Brown’s local support seems to be holding. State Sen. Audrey Gibson, a Jacksonville Democrat who has been mentioned as a possible successor to Brown, issued a statement Friday standing behind the incumbent.

“Congresswoman Brown has devoted countless hours to her constituents while balancing legislative and personal life, in a district that had suffered from institutional neglect for years,” Gibson said. “I look forward to her exoneration when the true facts are laid out.”

Those contributions, though, are largely unknown to voters outside of Duval County. Until now, they have seen Brown file a lawsuit to try to scuttle the redistricting plan and then get indicted.

Even before the indictment, the geographic trends of the district were clear. In a poll conducted June 27 and June 28 by the University of North Florida’s Public Opinion Research Laboratory, Brown held a narrow, three-point lead over Lawson among likely Democratic primary voters — well within the survey’s margin of error.

In the Duval County portion of the district, she led with 52 percent of the vote to Lawson’s 8 percent, with Holloway at 5 percent. But in the counties to the west of Jacksonville, Brown trailed Lawson by 26 points: 40-14, with Holloway at 3 percent.

In terms of population and voter registration, Jacksonville is still the center of the district. But Matt Isbell, a Democratic consultant and Lawson supporter, said that difference is essentially wiped out by turnout. The number of votes coming from Leon County and neighboring Gadsden County is larger than the portion of the vote turning out in Duval County.

“Someone like Lawson always was a threat, and it was going to come down to turnout,” Isbell said. “If Lawson wins the west as much as Corrine Brown wins Jacksonville and that turnout remains the same … then Lawson can win.”

Schale said that’s more likely now, given that Brown’s introduction to the new voters has been rocky. But he also cautioned against counting Brown out.

“I’m wise enough in my years (that) I don’t bet against Corrine Brown at this point in my life,” he said.

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The News Service of Florida’s Brandon Larrabee contributed to this report.