San Diego, California (CNN) A federal judge on Monday refused to dismiss the campaign finance violation case against California Republican Rep. Duncan Hunter.

In San Diego federal court, US District Judge Thomas J. Whelan rejected arguments from Hunter's attorneys that the case was politically motivated because two assistant US attorneys attended a fundraiser for Hillary Clinton and later brought the case against Hunter, who was one of the first congressmen to endorse then-candidate Donald Trump during the 2016 campaign.

The judge also tentatively denied a motion to move his September trial to a different venue, despite their arguments that the jury pool in San Diego would be tainted by the ample press coverage of Hunter's alleged misuse of more than $200,000 in campaign funds. The issue will be revisited during jury selection.

Hunter and his wife Margaret were indicted in August on charges that they misused a quarter of a million dollars to furnish a lavish lifestyle between 2010 and 2016 -- at a time when they were repeatedly overdrawing their personal checking account. They were charged with conspiracy, wire fraud, falsifying records and campaign finance violations. The San Diego County congressman's trial is set for September 10.

While Hunter has maintained that the couple's spending on the campaign credit card was an error, his wife has agreed to cooperate with prosecutors . In June she pleaded guilty to conspiring with her husband to "knowingly and willingly" convert campaign funds for personal use.

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