Congressman Steve Scalise of Louisiana, who was shot and injured on Wednesday while playing baseball in Virginia, is the majority whip of the House of Representatives, making him the third-ranking Republican there. He represents the First Congressional District in his home state of Louisiana, and has served five terms.

After the shooting at the practice for a congressional baseball team in Alexandria, Va., Mr. Scalise was undergoing surgery for a gunshot wound to the hip and was in stable condition, his office said in a statement. “Prior to entering surgery, the whip was in good spirits and spoke to his wife by phone,” the statement said.

Mr. Scalise, a self-described strong conservative leader, represents a district of Louisiana that stretches from the outskirts of New Orleans to the bayous. He was the establishment candidate in a 2008 special election to replace Bobby Jindal, who had become governor.

Known as an ambitous politician, once in the House, Mr. Scalise targeted the chairmanship of the Republican Study Committee, an influential caucus of conservative House members. As its chairman, he supported an alternative to the Affordable Care Act and backed other bills focusing on freedom of speech and the protection of constitutional rights.

He was elected in 2014 to serve as House whip, helped by a boost from Southern lawmakers who seemed to want one of their own in the position. The election capped Mr. Scalise’ rapid rise through his party’s ranks, after he won the 2008 special election.

Party whips in Congress are in charge of counting votes for and against legislation.

Mr. Scalise, 51, serves on the Energy and Commerce Committee, pushing for a national energy strategy that increases American energy supplies to reduce reliance on oil from the Middle East, according to a biography on his website.

Most recently, he has been vocal in his support for the repeal and replacement of the Affordable Care Act. Last month, after the House narrowly approved legislation to that end, he was among House Republicans who said that insurance markets in many states were already melting down, pointing to Iowa, where the last major insurer under the Affordable Care Act has threatened to pull out.

Mr. Scalise graduated from Louisiana State University in 1989 with a degree in computer science and political science. It was there, in the student assembly, that he got a taste for politics.

In 1995, Mr. Scalise, who worked at a small technology firm, wanted to run for the State Legislature. He served for four months in the Louisiana State Senate and 12 years in the Louisiana House of Representatives.

In 2014, his spokeswoman confirmed that he addressed a group of white supremacists and neo-Nazis in 2002, when he addressed the European-American Unity and Rights Organization, which was founded by David Duke, the former Ku Klux Klan leader and Louisiana politician. Mr. Scalise was a Louisiana state legislator at the time.

Moira Bagley Smith, a Scalise spokeswoman, said at the time that the congressman “has never been affiliated with the abhorrent group in question.”

Mr. Scalise is married to Jennifer Scalise, and the couple has two children.