A week before U.S. Rep. Michele Bachmann announced that she would not seek re-election next year, the top House GOP campaign official in Washington was asked whether, given the Minnesota Republican’s mounting legal problems, the party might not be better off running someone else.

“We are a member-driven organization,” said Rep. Greg Walden, R-Ore., chairman of the National Republican Congressional Committee. “We don’t recruit against our own members.”

Walden went on to express confidence in Bachmann’s national fundraising base, saying “she will figure out a way to win.”

It seems doubtful now that Bachmann had, as some of her supporters have suggested privately, the requisite “fire in the belly.”

Without any advance warning — not even to her Minnesota colleagues in Congress — Bachmann cut an eight-minute video announcing her decision, then released it in a 2 a.m. time slot designed to minimize press coverage.

Other than a friendly interview with Fox News Channel’s Sean Hannity, a financial supporter, the video provides the only public account Bachmann has offered so far on her decision to leave Congress at the end of her fourth term.

In the video, Bachmann avers that her decision was not driven by any fear of losing. Nor, she said, was it “impacted in any way by the recent inquiries into the activities of my former presidential campaign or my former presidential staff.”

But veteran Republican congressional aides have a difficult time imagining that the decision was based on anything but a clear-eyed calculation — based on polling — of her 2014 electoral prospects.

If her numbers looked anything like the Democrats’ numbers, she started essentially tied with then-DFL challenger Jim Graves in an overwhelmingly Republican district.

Analysts on both sides recognize that even a Bachmann under attack would have been difficult to beat. But adding to the insider skepticism about her sudden dedication to term limits was the timing of her announcement. It came merely two weeks after her campaign spent a reported $85,000 buying airtime in the Twin Cities to tout her leading role in the GOP battle against Obamacare.

What happened between the early ad buy and the decision to pull out?

Just as her constituents in Minnesota were waking up to the news on May 29, a judge in Iowa was scheduling a May 2014 trial date in a lawsuit accusing Bachmann and top officials from her 2012 presidential campaign of covering up the alleged theft of an Iowa staffer’s proprietary e-mail list.

That case is currently in settlement negotiations. But regardless of whether it’s settled, or forces her to answer questions in open court, the case was bound to be campaign fodder in the middle of an election year.

Bachmann’s decision also came as the independent Office of Congressional Ethics nears the end of a four-month-old probe of alleged improprieties involving her campaign finances and a personal book tour. The results of that inquiry could be referred to the House Ethics Committee, which at some point would have the authority to make them public.

She could be exonerated, of course. But the dripping sound of parallel investigations by the Federal Election Commission, the FBI, and various authorities in Iowa was bound to be a constant distraction. By announcing her retirement, Bachmann made all those legal and ethical problems seem a little bit smaller.

Bachmann has vowed to stay on the national scene. By retiring her House seat, she can do it on her own terms.