USSEAU, France — French presidential front-runner Emmanuel Macron hunted Saturday for votes in rural France where his far-right opponent, Marine Le Pen, is making inroads among people who feel left behind. Because many Dupont-Aignan voters had already been expected to switch to Le Pen for her runoff against the centrist Macron, the alliance is unlikely to prove a major electoral boost for her. Venturing into rural France to combat Le Pen’s arguments that he represents just the big-city elite, the former economy minister plugged his proposals to reverse the economic and social decline in farming areas. During an impromptu tour of the farmers’ market in the central town of Poitiers, Macron listened to a grain farmer complain about low-price competition from other EU countries and a vegetable farmer lament about the difficulty of getting loans to upgrade farm equipment. Macron rebuffed Le Pen’s criticisms of the EU with a vigorous defense of European free trade, saying her plans to leave the bloc and its agricultural aid program would spell the end of French farming.