INDIANAPOLIS — After a power struggle roiled the National Rifle Association’s annual convention over the last few days, the group’s board unanimously re-elected Wayne LaPierre as chief executive on Monday and selected a new president to replace Oliver L. North, attendees at its annual board meeting said.

The moves ended a bitter internal fight that pitted Mr. North, a right-wing celebrity since he emerged in the Iran-contra scandal, against Mr. LaPierre, the best-known face of the gun rights movement. They came as the N.R.A. is facing an array of challenges, including an investigation by the New York attorney general into the group’s tax-exempt status, and the new financial strength of the gun control movement. In a statement on Monday, Mr. LaPierre said he was “humbled by the board’s vote of confidence and its support of my vision for the future.”

Mr. North’s successor is Carolyn D. Meadows, a longtime member who was also elected unanimously, as the group did not seek to replace Mr. North with another celebrity. The N.R.A.’s presidency historically has been a largely ceremonial post, though Mr. North had sought to make it a paid one.

The power struggle began last Wednesday when Mr. North warned that unless Mr. LaPierre resigned, one of the N.R.A.’s top contractors would release “a devastating account of our financial status, sexual harassment charges against a staff member, accusations of wardrobe expenses and excessive staff travel expenses,” according to details provided in a letter Mr. LaPierre sent the next day to the N.R.A. board.