WAUSAU, Wis. — The Federal Aviation Administration is investigating what caused a small plane carrying U.S. Rep. Tom Tiffany to lose power before making an emergency landing in Lake Wausau on Saturday night. Tiffany, a Republican congressman and candidate for Wisconsin governor, and the pilot suffered minor injuries in the landing near Wausau Downtown Airport. The airport’s runway runs alongside the lake. Jeff Baum, president of Wisconsin Aviation and a pilot who has flown Tiffany previously, described the incident as unusual and rare. He said pilots train for emergencies but must make rapid decisions when a problem occurs unexpectedly. Baum said the two occupants appeared to have remained calm and benefited from several factors: The water was relatively shallow at the landing site, the aircraft came down close to shore and they were able to get out of the lake. The plane, a Beechcraft K35 Bonanza, landed upright. Tiffany said Sunday that the pilot’s decision to keep the landing gear up may have prevented the aircraft from flipping during the water landing. “We’re really fortunate that God was looking after us,” Tiffany said at a Sunday news conference, adding that the seriousness of the incident did not fully register with him until the following day. David Crowley, Tiffany’s Democratic opponent in the governor’s race, addressed the emergency landing at a Monday news conference. Crowley said political differences did not change his concern for Tiffany, the congressman’s family or the pilot. “At the end of the day, we may be political opponents, but we’re still human,” Crowley said. He also praised the pilot’s response and the first responders who assisted after the landing. The FAA’s investigation remained ongoing as of Monday. No cause for the loss of power had been identified publicly.