Rep. Kevin McCarthy (R-Calif.) pushes back on criticism that he isn't conservative enough to be the new House majority whip. (The Associated Press)

House Republicans dramatically reshaped their leadership team Thursday by selecting Rep. Kevin McCarthy (R-Calif.) to serve as the next House majority leader and Rep. Steve Scalise (R-La.) as the next majority whip.

The pair of fortysomethings who have spent less than a decade in Washington will help shape the Republican legislative agenda alongside Speaker John A. Boehner (R-Ohio) and steer the often rancorous GOP caucus through an intense period of legislative work on several spending matters leading up to November’s midterm elections.

McCarthy, 49, and Scalise, 48, were chosen Thursday in an unusual snap election caused by the surprising primary defeat of outgoing Majority Leader Eric Cantor (R-Va.).

McCarthy is serving his fourth term in Congress and his win makes him the fastest-rising majority leader in American history. A genial Californian, he is a strong fundraiser credited for his tireless work ethic, and has been cast as the candidate of the party’s establishment.

Scalise currently leads the Republican Study Committee, a caucus of conservative Republicans, and has been in office since 2008. A lifelong Louisianan, he has sparred frequently in recent years with Boehner, Cantor and McCarthy over spending matters.

Rep. Steve Scalise (R-La.) says he won a three-way race for majority whip because his coalition was united, and says his election is "a win for America." (The Associated Press)

McCarthy clinched the race during a closed-door election over his lone competitor, Rep. Raul Labrador (R-Idaho), who found it difficult to get votes beyond a small group of conservatives who helped him mount a failed coup against Boehner last year.

Scalise defeated two opponents — the current chief deputy whip, Rep. Peter Roskam (R-Ill.), and Indiana conservative Rep. Marlin A. Stutzman — and prevailed on the first ballot, a bold demonstration of how he quickly consolidated support in the past nine days.

He successfully rallied members of the RSC, most of whom are southern conservative Republicans whose numbers have swelled in recent tea party-fueled congressional elections. In a nod to his Cajun roots, Scalise distributed “Geaux Scalise” t-shirts and stickers that reminded colleagues of his ties to the Deep South.

“We built a strong team that was representative of our entire conference,” Scalise told reporters after the vote, adding later: “This is a win for America, because we’re going to be a united team moving forward.”

But Scalise’s election hardly calms the fear of many conservatives that the House leadership remains a more centrist group than the base of the party.

At 4 p.m., immediately following the leadership elections, Sen. Ted Cruz (R-Texas) sent an email to a large group of conservative House Republicans, inviting them to meet with him on June 24 for an “off the record gathering” and “an evening of discussion and fellowship.” Paul Teller, a Cruz adviser and former House staffer who clashed with Scalise while working at the RSC, is organizing the meeting. Pizza will be served.

Cruz, who was a player in last year’s federal government shutdown, has previously worked with several House members and urged them to pressure Boehner and Cantor to push a hardline conservative agenda.

McCarthy had moved quickly to lock up his win after Cantor’s loss by relying on his network of deputy whips and relationships he’s cultivated with colleagues, many of whom he recruited to run for office. With his victory locked up days ago, attention had shifted to replacing him as whip. The position is the third-highest in House leadership, responsible for counting votes and ensuring passage of Republican-backed legislation.

Several rank-and-filed Republicans emerged from the vote to say they were pleased.

“I think we’re going to see some new energy in the Republican leadership,” Rep. Joe Barton (R-Tex.) told reporters.

But Rep. Justin Amash (R-Mich.), who clashes frequently with GOP leaders and supported Labrador, expressed disappointment, saying that “the best chance for a change in leadership was today.”

Some conservatives criticized McCarthy and Scalise’s success and played down Scalise’s reputation as a voice for the House’s right flank.

“The bad news is that the two winning candidates, McCarthy and Scalise, are business-as-usual, go-along-to-get-along Washington insiders,” said Richard Viguerie, a longtime conservative activist. “The gap between the leadership of the Republican Party and the base of the party continues to widen.”

Results of the votes were not publicly released, but in a gesture of respect, Labrador asked that the vote for McCarthy be declared unanimous. According to lawmakers in the room, colleagues yelled out their approval.

The election of new GOP leaders began at 2 p.m. and lasted about 90 minutes.

Before the vote, with “Eye of the Tiger” playing in the staid Energy and Commerce committee hearing room, Scalise led his supporters out in a procession toward another room where votes would be cast.

“Alright,” Scalise said as he left the room. “Let’s go win.”

The process of electing new leaders mirrored the secrecy of a papal election and began with nominating and seconding speeches for McCarthy and Labrador, followed by the counting of ballots from the House Republicans. Supporters then nominated Scalise, Roskam and Stutzman and Scalise won quickly.

Cantor plans to relinquish his duties as majority leader on July 31, but will keep his House seat until the end of his term in January. McCarthy and Scalise are expected to spend the next six weeks hiring staff and preparing for the transition.

They will need to work quickly with Boehner on measures to replenish the nation’s highway construction fund; to reauthorize the Export-Import Bank; to revamp the troubled Department of Veterans Affairs; and to fund the federal government during the new fiscal year that begins in October.

Boehner provided few details on the pending legislation during his weekly news conference Thursday, but he conceded that the new highway bill will not mirror the ambitious, long-term agreement he has sought in the past. And he said he doubts that the cost of the bill to shore up the VA will be within current spending limits, meaning that several fiscally conservative Republicans might oppose the legislation.

Boehner made no reference to Thursday’s leadership elections other than to start his press conference by saying simply: “Happy election day.”

On Thursday morning, Scalise appeared confident that he could sweep on the first vote with many conservative Southerners behind him.

“No deals with anybody,” Scalise said as he stormed into his office, his phone pressed to his ear. “We’re going to win this thing.”

Cantor lost his primary race to little-known economist Dave Brat last week, a result that lawmakers and political observers agree will rank among the most stunning in American political history.

McCarthy, shocked by the results and pained for his good friend Cantor, quickly recalibrated and used his deep network of supporters and some old-school vote-counting techniques to seal the deal as other contenders were still mulling whether to join the fray.

When two well-known Texas conservatives, Reps. Pete Sessions and Jeb Hensarling, took a pass on challenging McCarthy for leader, Labrador launched a campaign, casting his candidacy as a necessary conduit for right-wing frustration with McCarthy’s otherwise uncontested rise in the wake of Cantor’s fall.

Wesley Lowery, David A. Fahrenthold, Paul Kane and Jackie Kucinich contributed to this report.