Though several high-profile speakers have dropped out, including Gov. Greg Abbott of Texas, several major political figures will attend the National Rifle Association’s annual convention in Houston after the massacre in Uvalde, Texas.

The most high-profile event of the three-day conference will begin at 2 p.m. Central on Friday. Scheduled speakers include former President Donald J. Trump, Senator Ted Cruz of Texas, Gov. Kristi Noem of South Dakota and Lt. Gov. Mark Robinson of North Carolina. It will also feature two top N.R.A. officials: Jason Ouimet, the executive director of the N.R.A.’s Institute for Legislative Action, and Wayne LaPierre, the N.R.A. vice president.

On Thursday, Gov. Abbott canceled plans to attend and will instead address the conference in prerecorded remarks while he returns to Uvalde.

Senator John Cornyn of Texas pulled out because he has to be in Washington for personal reasons, his office told Politico. Representative Dan Crenshaw of Texas told Fox News he canceled his appearance because he would not be back from a visit to Ukraine in time. Dan Patrick, the lieutenant governor of Texas, backed out of his speech at a breakfast on Friday because “I would not want my appearance today to bring any additional pain or grief to the families and all those suffering in Uvalde,” he said in a statement.

A musical performance scheduled for Saturday that was to feature several country music stars was in doubt after most of the artists backed out. Don McLean, Larry Gatlin and Larry Stewart withdrew on Thursday, followed by Lee Greenwood and T. Graham Brown.

Mr. Greenwood said in a statement that he canceled his appearance “out of respect for those mourning the loss of those innocent children and teachers in Uvalde.”

The N.R.A. said its “deepest sympathies are with the families and victims involved in this horrific and evil crime” and blamed it on “a lone, deranged criminal.”