On a warm, sun-splashed evening during final exams week, senior Matt Hochhauser knocks on doors on UW-Madison’s fraternity row. His mission: To get students who are preoccupied with studying and summer plans to think about an election that is just weeks away. “It’s very difficult because we have such a short amount of time to get people to vote,” said the English and history major from Long Island, N.Y., who was canvassing Langdon Street for the Democratic Party on Monday night. The timing of Wisconsin’s historic gubernatorial recall election couldn’t be worse for college students. Many will leave campus for the summer after exams end this week or graduation this weekend. Experts say the June 5 election between Republican Gov. Scott Walker and Democratic challenger Tom Barrett could result in lower turnout for a population that already votes in small numbers. “The barriers are huge,” said Elizabeth Hollander, a senior fellow at Tufts University who studies student civic engagement. “Not to knock college students, but they have a lot of other things on their mind.” Making things more complicated for the transitory population are new voting rules that require voters to live in an election ward for at least 28 consecutive days. People should vote at the residence where they lived on May 8, according to the Government Accountability Board. Students can file an absentee ballot if they are registered at that location but away for the summer.