The Star Tribune Editorial Board offers its recommendations to voters in a limited number of legislative primaries each election year. We confine our reach to the Twin Cities metro area and examine contests only within the dominant party in a district — that is, in situations in which the primary can be fairly deemed determinative of the ultimate election outcome.

Today we offer our picks in three state Senate contests on the Aug. 9 primary ballot. Our recommendations in several state House primaries will appear later this week. As always, we invite reader comments at startribune.com or letters to the editor submissions e-mailed to opinion@startribune.com:

Districts 59 and 62, DFL: Bobby Joe Champion and Jeff Hayden

It might be deemed a sign of desirable democratic vitality that intraparty challengers are nipping at the heels of two Minneapolis state Senate incumbents, Bobby Joe Champion, who serves downtown and the Near North Side in District 59, and Jeff Hayden, whose District 62 is immediately south of downtown. But it would be a mistake for voters to oust these two veteran legislators from a lawmaking body that rewards seniority with clout. Both should return to the Senate next year.

Hayden, 49, and Champion, 52, are the Senate’s only two African-American members. They are also friends who arrived in the Legislature together in 2009 and became lawmaking allies as they sought to bring state resources to bear on the needs of their inner-city districts. Hayden, a nonprofit manager outside the Legislature, quickly climbed into leadership ranks as deputy majority leader; Champion, an attorney, became vice chair of the powerful Finance Committee.

Their efforts to bring more economic opportunity to their districts culminated this year with their appointment as co-chairs of the Senate Finance Committee’s subcommittee on equity and the enactment of a $35 million package of grants and incentives in fiscal 2017 aimed at minority workforce development, plus an ongoing commitment of $17.5 million in subsequent years.

That measure was a considerable achievement in a year when other worthy initiatives faltered. But it is faulted as insufficient by primary challengers Patwin Lawrence in District 59 and Mohamoud Hassan in District 62. Both are making their first bids for elective office after years of activism. Lawrence, 39, is a Wells Fargo loan specialist and past chair of the Council on Black Minnesotans; Hassan, 42, has worked with East African Community Advocacy and hosted a radio talk show.

The challengers’ critique should remind Hayden and Champion not to rest on their laurels. But the challengers aren’t persuasive when they claim that they could do a better job for their districts in the next four years.

District 32, GOP: Sean Nienow

Is a private business failure sufficient reason to unseat a three-term state senator? Voters in District 32 think it is, Senate candidate Mark Koran claims. Koran says he’s challenging Sen. Sean Nienow of Cambridge for no reason other than concern that Nienow’s 2014 bankruptcy after default on a $613,000 Small Business Administration loan to his now-defunct camp referral business will lead to Nienow’s defeat if he’s on the ballot in November. The district’s Republican Party bought that argument and gave its endorsement to Koran.

We might be concerned, too, if evidence had surfaced that Nienow had traded on his legislative status to obtain the loan, reach a bankruptcy settlement or pay his personal debts. We also would be open to an argument that Nienow’s conservative positions on issues are too rigid for a once-rural district that is increasingly suburban.

Those are not Koran’s claims. He does not fault Nienow’s voting record and gives every assurance that, if elected, his would be at least as conservative. A former state Department of Revenue manager who helped develop electronic tax filing in the 1990s, Koran, 52, would bring to the Legislature expertise in government data systems and a bias toward privatization of government services. On other matters, he would face a steep learning curve.

Nienow, 48, is an energetic, accessible legislator who has led the charge for his party on several high-profile issues, including opposition to the financing deal struck for the new Vikings stadium. He has developed considerable expertise in education finance as ranking minority member on the Finance Committee’s E-12 budget division. We see no evidence that his financial problems have interfered with his public service, and no compelling reason for Republican voters to replace him with Koran on Aug. 9.