Wisconsin's U.S. senators have finally agreed on four potential nominees for a federal judgeship in Milwaukee and one of them could win President Donald Trump's nomination by this spring.

That would be quick, as far as federal judicial nominations go, said one expert. But the effort to fill the years-old vacancy has taken at couple odd turns already and there's no saying it won't face more unknown hurdles.

The same court is already down another judge; Chief U.S. District William Griesbach, who sits in Green Bay, announced last year that he would be taking senior status, a kind of partial retirement, beginning in 2020.

Last month, Republican Sen. Ron Johnson and Democratic Sen. Tammy Baldwin released the names they forwarded to the White House to fill a seat open on the U.S. District Court for the Eastern District of Wisconsin since the late Rudolph Randa took senior status in February 2016.

This list included Joseph Bugni, a federal public defender, Brett Ludwig, a U.S. Bankruptcy Court judge in Milwaukee, Daniel Vaccaro, a partner at Michael Best & Friedrich, and Samuel Hall, managing partner at Crivello Carlson.

Carl Tobias, a University of Richmond law professor who closely follows federal judicial selection, said that after a very active three years of filling higher-profile appellate court openings and naming two people to the U.S. Supreme Court, Trump could be ready to pick up the pace for trial-level district court judges.

He noted the vacancy rate among federal appeals courts is the lowest it has been in decades.

But will a possible impeachment trial in the U.S. Senate throw another big delay in confirming Trump's judicial nominees?

Possibly, but Tobias said the longer the impeachment trial is delayed, it might actually help fill the courts if senators use the time to try and clear their desks of other work.

"When they get (back from the holiday break) they could clear a bunch more" of the 30 district judges Trump has already nominated.

Trump's first try at filling Randa's spot on Milwaukee's federal court didn't work out. Late in 2017, he nominated one of Randa's former law clerks, Gordon Giampietro, for the job. His name had also come through the joint nominating commission.

Then reports surfaced about his 2014 radio interview comments highly critical of legalizing same-sex marriage and comments he made on a Catholic blog equating "calls for diversity" with relaxed moral and ethical standards.

Baldwin felt Giampietro had not fully disclosed all his comments and writings during the vetting process and withdrew her support. He never got a hearing before the Senate judiciary committee and Trump let his nomination expire at the end of 2018.

Tobias suggested at the time that the White House could have saved months of time if had just chosen one of the three finalists who had been named along with Giampietro — all current or former state court judges.

He said Trump could do the same thing now and nominate both Randa's and Griesbach's replacements from the four names Baldwin and Johnson sent him in December — that's if Trump gets around to nominating anyone from the list at all, given his own distractions of the impeachment and the 2020 re-election campaign.

From that group, two names appear to have the inside track.

Last summer, White House lawyers informed the co-finalists from the Giampietro list they weren't in the running, and, bypassing the nominating commission, sought names of conservative lawyers for the job.

Hall and Bugni were among six names that surfaced, and Hall was flown out to be interviewed at the White House.

But Baldwin said she wouldn't support any of the six because they hadn't gone through the traditional bipartisan nominating commission.

If Hall gets the nod, he would be the third openly gay Trump judicial nominee, after Mary Rowland now a district judge in Chicago and Patrick Bumatay on the U.S. Circuit Court of Appeals for the 9th Circuit.

U.S. District Court judges get lifetime appointments and currently earn $208,000 a year.

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Contact Bruce Vielmetti at (414) 224-2187 or bvielmetti@jrn.com. Follow him on Twitter at @ProofHearsay.