You have to hand it to David Vitter. He may not exactly ooze with charisma, and would probably elicit a squall if he tried to kiss a baby, but he is a born politician. He never loses an election.

His first was also the only one in which he had any reason to fear constituents might not find him sufficiently right wing. Republicans can forgive him, however, for that was in Metairie, 1991, when the incumbent, David Duke, was running for governor on a record of cross-burnings and Nazi raves.

Vitter, after seven years in Baton Rouge, won a seat in the U.S. House, moved up to the Senate in 2005 and cruised to re-election in 2010. Unless the polls are skewed as never before, he will face state Rep. John Bel Edwards, D-Amite, in the runoff after October’s gubernatorial primary.

Edwards has only one obvious disadvantage but it bids fair to be a fatal one. That D after his name might as well, in Louisiana these days, be a devil’s tail. So it appears that, if Vitter ever is to lose an election, it won’t be any time soon. He seldom puts a foot wrong on the campaign trail.

He’d certainly never miss such an easy opportunity to press a partisan advantage as the Hillary Clinton email investigation offers. He is hardly alone in raising suspicions of a cover-up, but he is, as usual, the one milking it to the max.

Polls show that even Democrats intending to vote for her doubt Clinton’s honesty, and her use of a private email account for official and sometimes top-secret communications in her days as secretary of state has not made her appear any less slippery. When it came to light that she had been conducting business outside official circles, she did turn over reams of emails to the State Department, but had deleted 30,000, claiming they concerned such personal matters as arrangements for daughter Chelsea’s wedding. Well, it was a big wedding.

No collegial spirit survives from the days when Vitter and Clinton were fellow senators, and he was one of only two to vote against her when she was nominated for secretary of state in 2009. He cited the huge donations the Clinton Foundation was accepting from dubious foreign sources.

Once confirmed, Clinton declined to designate Nigeria’s Boko Haram as a terrorist organization, a somewhat eccentric decision reversed by her successor, John Kerry, in 2013. Vitter, in a letter to Kerry, claimed Clinton had misled Congress over the Boko Haram threat, and wondered whether her stance had any connection with the $5 million donated to the Clinton Foundation by Nigerian land developer Gilbert Chagoury.

Vitter restated those concerns in another letter to Kerry a few months ago and asked that any Clinton emails relating to Boko Haram be released.

Now he takes up his pen, and the cudgels, again, writing this time to the inspectors general of the State Department and the intelligence community. He asks if they share his fear that their investigation of the Clinton emails may be stymied.

Vitter cites an opinion promulgated last month in which the Justice Department reserves to itself the right to decide what documentation shall be provided to inspectors general on the trail of government officials suspected of wrongdoing.

Inspectors general aren’t much use unless they are independent, and the timing of this opinion strongly suggests it was issued for Clinton’s benefit. When Vitter doubts that Obama’s Justice Department will be all that tenacious in holding Obama’s former secretary of state to account, he won’t find many dissenters.

Vitter could hit these out of the park all day. National Democrats are ensuring that his name pops up more or less daily in a favorable light as his campaign moves smoothly along.

Unless Clinton magically discovers some way of assuaging doubt about her integrity, or one of her rivals even more magically manages to snatch the nomination away from her, she will be a highly vulnerable presidential candidate. For Vitter, that will raise the prospect of a Republican House and Senate and a Republican president to complement his administration in Louisiana.

Of course, this state of affairs would be considerably less desirable from Vitter’s point of view if Gov. Bobby Jindal were our new president, since Louisiana’s top two Republicans hold each other in great contempt. But Vitter is too accomplished a politician to believe there is enough magic out there to put Jindal in the White House.

James Gill’s email address is