SPRINGFIELD, Mo. – Sen. Claire McCaskill said Wednesday she will vote against federal appellate judge Brett Kavanaugh, President Donald Trump's nomination to the U.S. Supreme Court.

Citing "dark money" in politics as the main reason for her opposition, McCaskill released a lengthy statement through her office Wednesday evening. The Missouri Democrat, who is in a heated re-election campaign, stumped in southwest Missouri earlier in the day with stops in Lebanon and Mt. Vernon.

At the Lebanon event, she minimized the importance of the sexual assault allegations leveled against Kavanaugh by Christine Blasey Ford, a California professor who has claimed Kavanaugh held her down and tried to take off her clothes more than 30 years ago when he was 17 and she was 15.

McCaskill called the allegations "disturbing" but said she would "set them aside" when deciding how to vote on Kavanaugh.

"I have been thorough in examining Judge Kavanaugh’s record," McCaskill said in the statement. "And while the recent allegations against him are troubling and deserve a thorough and fair examination by the Senate Judiciary Committee, my decision is not based on those allegations but rather on his positions on several key issues, most importantly the avalanche of dark, anonymous money that is crushing our democracy."

McCaskill has repeatedly said she was focusing on Kavanaugh's positions on anonymously sourced political spending, known as "dark money," when she was reviewing documents provided to senators. Her statement cited a 2002 email from Kavanaugh to another attorney as support for her criticism of the judge's views on money in politics.

"“He has revealed his bias against limits on campaign donations, which places him completely out of the mainstream of this nation," McCaskill said. "He wrote, ‘And I have heard very few people say that limits on contributions to candidates are unconstitutional although I for one tend to think those limits have some constitutional problems.’"

McCaskill said she believed Kavanaugh also would "give free reign to anonymous donors and foreign governments through their citizens to spend money to interfere and influence our elections with so-called ‘issue ads.’"

She cited a past opinion by the judge and other issues related to Kavanaugh's views in deciding to vote no.

“While I am also uncomfortable about his view on Presidential power as it relates to the rule of law, and his position that corporations are people, it is his allegiance to the position that unlimited donations and dark anonymous money, from even foreign interests, should be allowed to swamp the voices of individuals that has been the determining factor in my decision to vote no on his nomination," McCaskill concluded.

Her office added that McCaskill had voted for more than two-thirds of Trump's judicial nominees. Her Republican opponent, Attorney General Josh Hawley, has characterized McCaskill and Democrats in general as anti-Trump obstructionists and has called upon her repeatedly to confirm Kavanaugh.

McCaskill's "set them aside" comment regarding the allegations against Kavanaugh were cause for consternation and anger for some on social media after the News-Leader reported on her remarks earlier Wednesday.

UltraViolet, a women's advocacy group that opposes Kavanaugh, took to Twitter to urge McCaskill that the allegations were "part of Brett Kavanaugh's character."

"It will influence how he rules on decisions that impact women," the group said. "We can't have someone like that on the Supreme Court."

Kavanaugh has denied Ford's allegations. Both have been invited to testify before the Senate Judiciary Committee next week.

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