American politics needs a makeover, and Emmanuel Macron might be the man to do it. Sure, the technocrat-turned-president has a lot on his plate right now — compelling stuff like recasting France as an innovative tech hub, rejiggering his country’s archaic work rules and reviving its flagging economy. But if he ever has a moment to spare away from the demands of international diplomacy and arm-wrestling President Trump, the mediagenic politician who came out of nowhere to win a hotly contested race could give his counterparts in the United States a master class in playing the image-manipulation game.

For a start, he could offer pointers on how to use clothes to political advantage, as he did throughout his canny presidential run. Before this novice of the campaign trail became, at 39, the youngest man ever elected president of France, Mr. Macron had been a banker and a minister of economy and finance, one who dressed in the chic, uptight uniform of the power elite: pinstripe suits, white shirts with modest spread collars, anonymous silk ties.

Whatever he may have lacked in campaign experience Mr. Macron made up for in nimble adaptation, adjusting his wardrobe according to how he polled. If initially his sartorial style was said to “reek of health, vigor and physical prowess,” as one fashion expert observed before the election, it also read as insufficiently populist. Yet no sooner had the press gotten wind of the hefty price tags on the dark suits that seemed to cloak the slightly built Mr. Macron in authority than a tailor was found to make him a cut-rate version. Forgoing the pinstripe Lagonda suits he had favored as a banker, Mr. Macron hit the campaign trail in navy or dark gray models stitched for him by Jonas et Cie, a traditional tailor in Paris’s onetime garment district.

Back when he was dressing in outfits that cost 1,200 euros (about $1,400), Mr. Macron found himself vulnerable to criticism from those in his former (Socialist) party. Just by losing the hand-stitched buttonholes and the smart silk linings, he saved himself roughly $800 a suit and simultaneously gained himself a measure of voter approval — appreciation for a cost-value proposition being as deeply Gallic a quality as a love of Serge Gainsbourg.