This was a busy week in politics -- but then, practically every week is. That's why Governing is offering this new weekly newsletter.

We won't cover the presidential campaign -- you can find plenty of that elsewhere. Instead, we aim to share with you the most interesting and important developments in state and local politics each week.

You can sign up for a free subscription here.

Flint Curbs Snyder's Future

Although it's premature to call him a lame duck, Michigan Gov. Rick Snyder's political capital has clearly been diminished by the Flint water crisis. During his State of the State address on Tuesday, Snyder offered lots of apologies: "You did not create this crisis;" “Government failed you;” and, “I'm sorry."

Since winning re-election in 2014, Snyder had been mentioned as a potential presidential or vice presidential pick on the Republican side. That kind of talk, however, has abruptly ended. "Even some Michigan Republicans concede that Snyder’s national prospects are toast, at least in the short term," reports Politico.

At home, Snyder faces protesters calling for his resignation and arrest. Neither of those are likely to happen, but it's undeniable that his reputation and ability to lead have been damaged.

GOP lawmakers in Michigan tend to be more conservative than Snyder and are still angry with him for making more low-income people eligible for Medicaid and increasing taxes to pay for roads. On top of that, the Flint water crisis has eroded Snyder's ability to push his agenda on other issues.

"The governor had hoped to focus this year on politically tough issues like parole reform, energy policy and the Detroit Public Schools," said Susan Demas, editor and publisher of the newsletter Inside Michigan Politics. "But now Flint has overridden everything."

Court May Tie Corruption Prosecutors' Hands

It's always hard to convict public officials of corruption, and the U.S. Supreme Court may soon make it harder.

The justices decided this week to hear an appeal from former Virginia Gov. Robert McDonnell, who was convicted of corruption in 2014 and faces a two-year prison sentence for accepting $175,000 and gifts from a businessman in exchange for helping to promote his product.

McDonnell's attorneys argue that his conviction "criminalized ordinary politics." He might have accepted large gifts from someone seeking to do business with the state, they say, but what politician hasn't? "This is the first time in our history,” his attorneys wrote in a brief, “that a public official has been convicted of corruption despite never agreeing to put a thumb on the scales of any government decision.”

The Obama administration disagrees. Its lawyers argue that McDonnell clearly broke the law by using "his position to influence government matters on behalf of his benefactor” and urged the justices to uphold his conviction.

The line between political dealmaking and criminal activity has long been blurry -- a point that longtime Governing editor Alan Ehrenhalt argued last year. “The rickety character of criminal law as applied to the behavior of public officials," he wrote, shows that the way campaign finance systems work in this country make it almost impossible to separate illegal acts from the normal course of politics.

By agreeing to hear the McDonnell case, the nation's highest court could clear up that confusion, particularly if it throws out the charges, dampening the ability of prosecutors to prove wrongdoing. In recent cases, justices have expressed skepticism that anything amounts to corruption unless there's an explicit trading of favors for cash -- but it's unlikely prosecutors will find many politicians who perform favors for friends and then write out receipts.

'Spending Money to Demonize Each Other'

Candidates for Missouri governor released their fundraising totals last Friday, and Democratic Attorney General Chris Koster -- who faces no challenge within his own party – remains well ahead of his GOP rivals.

Koster started the year with nearly $6 million in the bank. None of his four Republican rivals had more than $3.6 million. While Republicans dominate the legislature, Democrats hold most statewide offices, including the governorship, which is being vacated by term-limited Jay Nixon.

This year's race has already proven divisive for the GOP, and the party won't select its nominee until the August primary. But that doesn't make the race a slam-dunk for Koster. Instead, it affords him the luxury of planning -- and raising money -- for the fall.

"While Koster hoards his financial resources and enjoys the opportunity to pick and choose his political battles, the candidates campaigning on the Republican side will be spending money to demonize each other," said Peverill Squire, a political scientist at the University of Missouri. "By the time Republican voters make their choice in August, the possibly damaged winner will have only a few weeks to generate more funds to take on Koster."

Odds and Ends

New GOP Supermajority: In Mississippi, Republicans won supermajority control of the state House this week through a move that's certain to rankle partisan feelings. Last November, Democratic state Rep. Blaine Eaton's re-election bid ended in a tie between him and Mark Tullos. He subsequently drew the long straw (literally) in a tie-breaker. But on Wednesday, Tullos was instead pronounced the winner by the House, which found that the race should never have been called a tie, throwing out five provisional ballots.

Billionaire's Bid: Software billionaire Greg Gianforte made official his pursuit of the Republican nomination for Montana governor on Wednesday. He'll face incumbent Democratic Gov. Steve Bullock. "#mtgov will arguably be the premiere 2016 gubernatorial race," tweeted Nick Riccardi, western political reporter for the Associated Press.

Cautious in California: For the second time, former San Jose Mayor Chuck Reed and former San Diego City Councilman Carl DeMaio have backed off from plans to put a proposal to limit public workers' pensions on the California ballot. They vow to try again in 2018.