President Obama's nomination of Minnesota U.S. Attorney B. Todd Jones to head the Bureau of Alcohol, Tobacco, Firearms and Explosives cleared a key Senate panel Thursday, setting up a potential floor fight with Republican opponents.

The 10-8 party-line vote in the Senate Judiciary Committee capped six months of behind-the-scenes maneuvering marked by increasingly personal attacks on Jones' management style as Minnesota's top law enforcement officer and as acting ATF chief.

The nomination battle also has played out against the backdrop of Obama's gun control agenda after the December school massacre in Newtown, Conn.

Facing a potential GOP filibuster, Democrats would have to secure at least six Republican votes to install Jones as the permanent head of the ATF, an agency he has led as acting director for the past two years.

Minnesota Democrats Amy Klobuchar and Al Franken, both members of the judiciary panel, voted for Jones' nomination.

"Todd Jones has done two crucial jobs for two years, serving as both acting director of the ATF and U.S. attorney for Minnesota," Klobuchar said. "The ATF needs a permanent leader, and today's vote is a step in the right direction."

Democrats noted that the gun lobby and its Republican allies in Congress have objected to every ATF nominee since the Bush administration, when the agency split off from the Treasury Department. "After nearly seven years without a permanent ATF director, it's long past time that we confirm one," Franken said. "I think that B. Todd Jones is a good candidate for the job."

Complicated by infighting

Jones' nomination has been complicated by infighting in the U.S. attorney's office in Minneapolis, some of which dates to the controversial Bush-era appointment of Rachel Paulose, who left amid reports of staff turmoil. Allegations of cronyism and political favoritism have likewise dogged Jones.

Iowa Sen. Charles Grassley, the ranking Republican on the judiciary panel, had tried to delay the vote on Jones' pending mediation in a whistleblower complaint brought by Jeffrey Paulsen, an assistant U.S. attorney in Minneapolis. Paulsen, a veteran prosecutor, says he was unfairly disciplined by Jones for raising management concerns.

"I do not believe we should simply rubber-stamp this nomination and sweep the alarming allegations under the rug," Grassley told the panel Thursday. "So I would hope that further action on the nomination be paused until these matters are closed."

Although GOP opposition was unanimous on the committee, Grassley was the only Republican to attend the late-afternoon vote, which had been pushed back from the morning. The other seven Republican votes against Jones were cast by proxy, which is allowed under Senate rules.

Grassley requested last week that the Obama administration turn over documents that might reveal "conflicts" and other "expressions of dissatisfaction" with Jones. The requests were made to heads of the Federal Bureau of Investigation, the Drug Enforcement Administration and U.S. Immigration and Customs Enforcement.

White House: Stop excuses

The White House has not publicly responded to Grassley's latest document request. But in an earlier statement, Obama spokesman Jay Carney called on Republicans to "stop coming up with excuses to obstruct a highly qualified nominee and finally put a confirmed director at the helm of a critical law enforcement agency."

Along with three unnamed Minnesota law enforcement critics, Grassley invoked a letter from former Minnesota FBI chief Donald Oswald, who said Jones had an "atrocious professional reputation" in Minnesota.

Democrats countered with letters from other top law enforcement figures who praised Jones' work. The latest was a June 25 letter from Ralph Boelter, head of the FBI's Minneapolis division from 2007 to 2011, who said he "enjoyed a close and productive working relationship" with Jones.

Grassley and other Republicans have clashed with Jones over prosecutorial priorities, particularly on gun crimes, which Republicans say go unenforced while gun-control advocates press for new laws.

In a hearing last month, Grassley pressed Jones on the ATF's reforms after the botched gun-tracking operation on the Mexican border known as Fast and Furious, which took place before Jones joined the ATF.

Jones' nomination also has been caught up in the broader debate over the administration's failed post-Newtown initiatives to expand background checks on gun buyers and ban assault-style semi-automatic weapons.

While Republicans have made no specific threats to block a floor vote on Jones, analysts say his fate could be decided by filibuster reform talks in the Senate in the coming weeks.

Follow Kevin Diaz on Twitter at @StribDiaz.