There's a House leadership shakeup after Majority Leader Rep. Eric Cantor, R-Va., lost his primary -- and with it, his seat in Congress. That leaves the majority leader position open, plus questions about who will step in as the Republican whip. But what do a majority leader and whip do, anyway? The Fix's Chris Cillizza has all you need to know. (Julie Percha/The Washington Post)

With House Majority Whip Kevin McCarthy (R-Calif.) expected to easily ascend Thursday to the majority leader role being vacated by Eric Cantor (R-Va.) in July, the scramble by the three candidates hoping to replace McCarthy dominated the Capitol’s marble halls on Wednesday.

McCarthy has all but clinched his race, with his lone competitor, Rep. Raul Labrador (R-Idaho), finding it difficult to get votes beyond the conservatives who, with him, mounted a failed coup against House Speaker John A. Boehner (R-Ohio) last year.

How Republicans elect their leader: a primer

Rep. Steve Scalise (R-La.) is campaigning to be House majority whip ahead of Thursday’s House leadership vote. (Melina Mara/The Washington Post)

Leading House Republicans such as Rep. Paul Ryan (R-Wis.) and most committee chairmen have endorsed McCarthy, calling him the consensus candidate at a tumultuous time.

Thursday’s leadership elections, called after Cantor was defeated in a stunning primary upset last week by a little-known challenger, have reopened a rift between the establishment and fiercely conservative wings of the House Republican Conference — as both groups vie for a leadership post that will shape the ideological path of the party for the remainder of this Congress.

The three-way whip race — which pits well-connected Republican Study Committee Chairman Steve Scalise (R-La.) against the current chief deputy whip, Rep. Peter Roskam (R-Ill.), and youthful Indiana conservative Rep. Marlin A. Stutzman — seems increasingly likely to require multiple votes, a possibility that adds an element of unpredictability to a contest in which Scalise seems to have built a sizable advantage in recent days.

All three men spoke early Wednesday to Republicans gathered in the basement of the Capitol. They sipped coffee and snacked on doughnuts and bagels as each of the three made his pitch.

Roskam’s speech at the morning forum, which featured a surprisingly rightward slant for a member known for his mild manners and low-key management style, was seen as a play for those conservatives still on the fence. His voice was urgent, coming a day after some of his allies urged him to show some fire.

“The disconnect that I’ve heard this morning is a symptom,” Roskam said minutes after some Republicans sparred over the House’s ideological drift. “Our base has lost confidence in us. Our base doesn’t feel like we’re reflecting their rage. We need to communicate our deep convictions.”

Stutzman framed the House GOP as a baseball team and stressed the need for teamwork. Scalise struck a similar tone, declaring: “What unites us is that we all have the same passions to fix problems in the country.”

When Republicans meet Thursday afternoon, a candidate will have to secure 117 votes to win 51 percent of the 233-member GOP conference and become whip. With Scalise’s advisers claiming he has more than 100 votes and Roskam allies saying he has amassed at least 90, attention has turned to Stutzman and the politics surrounding a second ballot.

If no candidate amasses an outright majority on the first ballot, the lowest vote-getter would be dropped from the ballot and a second vote would be held between the remaining two contenders.

Stutzman, who claims to have secured about 50 votes, has remained coy about his potential role as kingmaker.

Off the House floor Wednesday, Stutzman said he is unsure whom he would support if he falls short and that he was not advising his supporters on a second-ballot preference, even when pressed. “I don’t have an answer yet,” he said, chuckling at the speculation about his intentions.

Stutzman’s poker face gives him leverage Thursday, with both Scalise and Roskam clamoring to win over him and his backers, many of them fellow sophomores, such as Rep. Sean Duffy (R-Wis.) and Rep. Thomas W. Reed II (R-N.Y.).

Some Scalise and Roskam allies have said that if the race is close, Stutzman could be offered the position of chief deputy whip in an effort to get him and his team on board ahead of the second vote.

The whip race has plowed a divide in the House GOP caucus, with many southern and tea party members insisting that the deputy whip position be filled by a Republican hailing from a red state. Many of those conservatives have rallied around both Scalise and Stutzman.

Rep. Darrell Issa (R-Calif.) told reporters Wednesday that he supports Scalise but refused to say if he would back Scalise on a second ballot.

“I don’t play those games,” Issa said.

Issa’s reluctance to comment on how he would vote beyond the first ballot reflects the sense of intrigue on Capitol Hill about how Thursday’s vote will ultimately play out — and the feeling of many of his colleagues who have publicly pledged support for one candidate but remain open to discussing how they would tilt in a second round.

Former congressman Tom Davis (R-Va.), who was at the Capitol on Wednesday, said that when there is a secret ballot, the pre-vote tallies of purported support may not be what they seem.

“The only member you can believe is the one that looks you in the eye and tells you they are voting against you,” he said.

Roskam’s supporters, knowing their candidate is lagging slightly behind Scalise, are pleading with members to back the Illinoisan if the race comes down to Scalise and Roskam, arguing that he will owe his victory to them — and remember it.

Making the case for Roskam on Wednesday was Rep. Pat Tiberi (R-Ohio), a top ally of Boehner, and Rep. Trey Gowdy (R-S.C.), a tea party favorite.

Rep. Richard Hudson (R-N.C.), a strategist for Roskam’s whip campaign, said Wednesday that he believes about 20 House Republicans remain undecided, most of them on the conservative side.

Roskam’s camp said that although Scalise may be seen as more conservative, his support among them is fragile, due to disagreements over his management and policy maneuvers within the Republican Study Committee, a caucus Scalise chairs. Scalise’s shake-up of its staff and his friendly relations with McCarthy have also irritated some hard-liners.

Roskam’s advocates have reassured skeptical Southerners that should he win, he will appoint a “red state” member as his deputy and that he will be a conduit for them, even though he hails from a solidly blue state. Last week, in a letter sent to all House Republicans, Roskam wrote that it is “more important to have the skills necessary to line up votes than to check a geographical box.”

All three whip candidates spent the afternoon making final overtures to different factions of the Republican conference – making stops at a lunch with Southern lawmakers and the Tuesday Group — made up of the House GOP’s moderate members.

Asked about how the meeting with the Southerners went, Roskam said they reiterated the importance of having their region represented in leadership.

“They are right, and we need to do better,” he said as he walked into his first-floor Capitol Hill office.

But some conservative groups see Roskam, a 52-year-old attorney, as a middle-of-the-road Republican, with Heritage Action rating him at 52 percent, 10 percentage points less than the House GOP average. The American Conservative Union rated him last year at 76 percent — well below Scalise, who earned a perfect score.

Scalise’s advisers said they think Stutzman’s supporters, even if they have had differences with Scalise, will endorse Scalise in a second round, hoping to send a message to the leadership about the need for more ideological and geographical balance.

“We’re looking for a new voice at the leadership table, and we clearly bring that,” Scalise said as he made his way into the Wednesday morning candidate forum.

Almost two hours later, as he left the meeting room, he added, “rather be us than them” in response to a reporter’s question about whether he had reached 117 votes.

Ultimately, support from Stutzman and his prominent booster, tea party leader Rep. Jim Jordan (R-Ohio), could end up being a deciding factor in a race that has tightened.

Meanwhile, Stutzman’s bid has given him a higher profile within the House GOP, and he said he was open to considering future leadership posts, including another leadership run in the coming years. Running for chairman of the Republican Study Committee is seen as a logical next step.

“I love the RSC,” Stutzman said, when asked about whether he was mulling a run to lead the right-wing caucus. “It just hasn’t been settled in my gut.”

More likely is that Stutzman would use his higher profile for a later leadership run, perhaps for majority whip or conference chairman when an opening emerges.

“I wouldn’t rule it out, maybe not next time, but down the road again,” Stutzman said.

Jackie Kucinich contributed to this report.