After waiting months to weigh in on Supreme Court nominee Brett Kavanaugh, Democratic Sen. Joe Donnelly on Friday said he was opposing the nomination after considering the sexual assault allegations against the judge.

Donnelly’s decision came hours before the Senate Judiciary Committee voted along party lines to send the nomination to the full Senate. Donnelly, in a tight Indiana race for re-election to a second term, was among a handful of senators who had remained undecided and whose votes could be key in deciding Kavanaugh's fate on the Senate floor.

“As I have made clear before, sexual assault has no place in our society," Donnelly said in a prepared statement. "When it does occur, we should listen to the survivors and work to ensure it never happens again."

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Donnelly's potentially pivotal vote on Kavanaugh is likely to be a key issue in his re-election battle with GOP challenger Mike Braun in a state that voted strongly for President Trump amid his pledge to appoint a more conservative Supreme Court.

Braun, a businessman from Jasper, said Friday he continues to strongly support Kavanaugh's nomination.

"This entire process has been an embarrassment to our democracy as Hoosiers watched firsthand how Senator Donnelly’s liberal colleagues used uncorroborated allegations to create a media circus designed to smear and destroy Judge Kavanaugh’s reputation," Braun said in a statement. "Donnelly’s decision to oppose President Trump’s highly qualified nominee is a grave mistake, but proves he is more concerned with standing with his liberal Democrat leaders than standing for Hoosiers."

Before the allegations of sexual assault, political watchers say Donnelly likely would have voted for Kavanaugh based on the political tightrope he walks as a moderate Democrat in a conservative-leaning state. Trump won Indiana by 19 percentage points in 2016.

As Donnelly announced his opposition to Kavanaugh, he made it clear he’d "welcome the opportunity to work with President Trump on a new nominee."

Andy Downs, a political scientist at Indiana University-Purdue University Fort Wayne, said the allegations of sexual assault gave Donnelly cover to vote against Kavanaugh.

Moderate voters, especially suburban women, are concerned by the accusations, Downs says, even if they liked Kavanaugh's ideological viewpoints.

“With Joe Donnelly, we have somebody who has always been able to explain why he voted for some and against some various nominations,” Downs said. “Yesterday, I think he saw enough that would allow him to vote no.”

Still, Republicans clearly hope to use the decision against Donnelly. The Indiana GOP issued a statement on Twitter shortly after Donnelly's announcement criticizing his stance while including the hashtag #ConfirmKavanaugh.

"Democrat Joe Donnelly just turned his back on Hoosiers & will vote against confirming President Donald Trump's well-qualified nominee for the U.S. Supreme Court, Judge Brett Kavanaugh" the Indiana GOP Tweeted.

Donnelly had supported Trump's first nominee to the Supreme Court, Neil Gorsuch, but said he could not support Kavanaugh due to the allegations of sexual assault by professor Christine Blasey Ford. Donnelly said the “disturbing and credible” allegations should be investigated by the FBI.

“I have deep reservations about Judge Kavanaugh’s nomination to this lifetime position," Donnelly said, "and, as I stated, we have been unable to get all the information necessary regarding this nomination, despite my best efforts."

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In an unprecedented move, the American Bar Association Friday also also asked the committee to halt the process to allow the FBI to investigate the claims.

Sen. Jeff Flake, R-Arizona, decided Friday to cast a key vote that allowed the judiciary committee to send the nomination to the full senate but said he wanted an FBI investigation of the allegations against Kavanaugh before the floor vote. Trump ultimately agreed to reopen the FBI probe.

With Republicans holding a 51-49 majority, it’s unclear whether the GOP will be able to hold the line and confirm Kavanaugh strictly along party lines. They can only weather one defection, so long as Vice President Mike Pence casts the tie-breaking vote.

As of Friday afternoon, Sens. Lisa Murkowski, R-Alaska, and Susan Collins, R-Maine, had not announced how they would vote once the nomination reaches the full Senate.

Donnelly had been among that handful of undecided senators who could determine Kavanaugh's fate.

Democratic Sens. Joe Manchin of West Virginia and Heidi Heitkamp of North Dakota — all facing re-election challenges — remained undecided Friday afternoon. Jon Tester of Montana, another vulnerable Democrat, announced Friday afternoon that he too would vote against Kavanaugh's confirmation.

Indiana's junior senator, Republican Todd Young, announced his support for Kavanaugh late Thursday.

Call IndyStar reporter Chris Sikich at 317-444-6036. Follow him on Twitter: @ChrisSikich and at facebook.com/chris.sikich.

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