But there's never been a presidential candidate like Donald Trump, and while the billionaire's willingness to buck convention has been a strength in the tumultuous 2016 race, it came with a downside Wednesday.

Any other candidate would be embraced by his party as a conquering hero after Tuesday night's wins. Instead, he's getting the cold shoulder reserved for an especially obstinate unwanted guest from GOP leaders who see him as a toxic influence that could cost them the White House and Senate -- and leave a stain on the party of Lincoln, if not tear it apart.

Trump might have cemented his role as front-runner in the GOP race, but he now faces a tricky period as he tries to put the nomination truly beyond reach of his rivals, and not only the ones on the ballot. He faces accelerating efforts by conservatives and establishment figures alike to thwart his White House dreams at the 11th hour.

"We all agree Trump as the nominee would be a disaster morally, politically, and electorally. Well, then, let's do something about it," prominent talk radio host Steve Deace, who has endorsed Texas Sen. Ted Cruz, wrote in a Facebook post late Tuesday.

Trump, however, dismissed any suggestions at a Tuesday night victory lap press conference that he would be a divisive force in the party.

"I'm a unifier," Trump said. "I know people are going to find that a little bit hard to believe, but believe me."

GOP politicians repudiate Trump

Some lawmakers are also beginning to break with precedent and repudiate the party's front-runner. Nebraska's Republican Sen. Ben Sasse said over the weekend he won't vote for Trump even if he becomes the nominee.

And Virginia GOP Rep. Scott Rigell warned on "The Lead" with Jake Tapper Wednesday that he would not vote for Trump either, arguing that he lacked judgment on foreign policy and was not fit to be commander in chief.

"This extremis moment that we are in, in our country -- the solution is not Donald Trump," Rigell said. "I truly believe he would harm our country."

Yet many Republican voters feel differently. Trump enjoyed a seven-state romp on Super Tuesday to take his primary and caucus win total to 10. Traditionally at this point he'd be wallowing in the plaudits of his party and tasting the power endowed by his first few hours as its presumptive presidential nominee.

After winning a swath of states with diverse ideological, geographical and demographic profiles, like Trump has, such a candidate would expect his main foes to fold their campaigns to fall in behind him -- especially in an election likely to feature Democrat Hillary Clinton, a rallying point for GOP hatred for decades.

Instead, Trump must brace for a torrent of revelations from his own side about his business practices, his personality, what he really believes behind closed doors and questions on whether he's qualified to preside over a nuclear arsenal from opponents who balk at his takeover of their party.

It could be an onslaught with far more punch than the nascent #NeverTrump meme on Twitter -- started by Republicans.

As an anti-Trump movement gathered force Wednesday, former Republican nominee Mitt Romney scheduled a high-profile speech on the race on Thursday in which he's expected to criticize Trump. GOP candidate Ben Carson pulled out of Thursday's Republican debate and told supporters in a press release Wednesday that he saw no path forward, in a move that could help Trump rivals Cruz or Florida Sen. Marco Rubio.

South Carolina Sen. Lindsey Graham, who dropped his own presidential campaign before the Iowa caucuses, said he would back Cruz over Trump because Trump is an "interloper" and not a real Republican.

"Ted and I are in the same party. Donald Trump is an interloper," Graham told CNN. "I don't trust him."

And doubts over Trump are not confined to his politics in a year in which conservatives had high hopes of nominating the most ideologically pure nominee since Ronald Reagan.

There is also deep skepticism among some conservatives about his behavior and explosive rhetoric as well. Many Republicans feel Trump's emotive language toward groups including Mexicans, women and Muslims is disqualifying.

"This is a guy who has made, shall we say, racially insensitive remarks, things that conservatives who care about defending the cause of conservatism cannot in good conscience abide," said Matt Lewis, a CNN commentator and author of a new book that argues the Republican Party has betrayed its conservative roots.

JUST WATCHED Donald Trump's Super Tuesday press conference Replay More Videos ... MUST WATCH Donald Trump's Super Tuesday press conference 30:46

Former Republican House Majority Leader Tom DeLay told CNN's Brooke Baldwin that he hoped Romney would lead an effort to explain that the race is not over.

"Trump ought to take a pause. He lost four states last night, which shows he is vulnerable. He only has right now 300 delegates. He needs 1,237," DeLay said.

DeLay is technically correct that Trump has yet to put the nomination out of reach of Rubio and Cruz. The theory of his opponents is that once more states hand out delegates on a winner-take-all basis after March 15, his lead of around 100 delegates over Cruz and 200 over Rubio could be overhauled should either of them start claiming more first-place finishes. Ohio Gov. John Kasich is also hoping to stack up delegates when the race hits the Midwest.

At the very least, Trump opponents hope to prevent the real estate mogul from harvesting sufficient delegates to clinch the nomination before the Republican National Convention in Cleveland, Ohio, in July.

Advantages for an unconventional candidate

But Trump has advantages that could blunt any organized GOP bids to thwart him -- just as he has succeeded in bending the contours of the presidential race to his will throughout his campaign.

In his press conference on Tuesday night, he several times delivered a veiled warning to Republican Party leaders that they would be taking on more than just his campaign if they resorted to attacks on his character.

"But remember this. I have millions and millions and millions of people," he said in a possible reference to his earlier warnings that he could bolt the party and mount an independent bid for president if he was not treated fairly.

No other candidate has greater momentum or a greater claim to the nomination at this point. His closest rival, Cruz, has only won four states and Rubio just one. A bid to wrest the party banner away from his hands would risk alienating his fervent supporters, who might then repudiate any subsequent nominee that emerges.

Furthermore, Trump's strength in recent Southern nominating contests suggests he will run strongly in primaries and caucuses in places like Louisiana and Kentucky Saturday and next week in Mississippi. The Rubio camp's theory that a victory in his home state of Florida on March 15 will buckle the billionaire's hopes of the nomination is undercut by a recent Sunshine State poll showing Trump with a clear lead.

In another odd twist, Trump's loss in Texas, the biggest state of Super Tuesday with 155 delegates, may have actually helped him, since Cruz's win gave him a rationale to stay in the race. That ensures opposition to the billionaire will remain fractured for a few more weeks at least.

And while it is possible to pick holes in Trump's path to the nomination, his route is far more credible than those of his rivals.

Many pundits have long suggested that Trump has a ceiling of around 30% in the polls and would slump once the field narrowed.

But he hit 49% in Massachusetts, 39% in Tennessee and 43% in Alabama on Tuesday. In a new CNN national poll this week, Trump reached 49% support among all Republican voters.

Photos: Donald Trump: His own words Photos: Donald Trump: His own words Hide Caption 1 of 6 Photos: Donald Trump: His own words Hide Caption 2 of 6 Photos: Donald Trump: His own words Hide Caption 3 of 6 Photos: Donald Trump: His own words Hide Caption 4 of 6 Photos: Donald Trump: His own words Hide Caption 5 of 6 Photos: Donald Trump: His own words In his interview with CNN's Dana Bash, Donald Trump lashes out at a lawyer who had requested a break to pump breast milk in the middle of a deposition. Hide Caption 6 of 6

In a bid to underpin his wins on Super Tuesday, Trump argued at the press conference that he was a "unifier" and took immediate aim at Clinton, possibly to help GOP voters envisage a presidential race that could bring the party together, its numbers swelled by new Trump voters.

"We are expanding the party," he said. "Once we get all of this finished, I am going to go after one person -- that is Hillary Clinton."

And in a possible sign of a tack Tuesday towards female voters important in a general election -- who may feel alienated by his rhetoric -- Trump noted that millions of women had been helped by Planned Parenthood, an organization reviled by conservatives.

Still, not all of Trump's positioning appears to be working. If securing the endorsement of New Jersey Gov. Chris Christie was meant to confer establishment approval on his campaign, it backfired. The former GOP presidential candidate has been widely lampooned over a move that seemed to fly in the face of his previous criticisms of Trump's fitness to serve as president. And Christie became the subject of Twitter mockery over his apparent discomfort on stage during Trump's news conference on Tuesday night.

Warning signs for Trump?

And there were some warning signs in the results on Tuesday. Following predictions that he could sweep up to 10 Super Tuesday states, Trump had to content himself with seven. He faced a tougher fight in a crucial swing state -- Virginia -- than polls had predicted, in a sign that not all Republican voters are reconciled to having the former reality star as their presidential nominee.

Exit polls showed that voters who made up their minds there in the last few days chose Rubio, a possible indication that the Florida senator's furious attacks on his rival's character and business record may have had an impact over the last week.

"Five days ago, we began to explain to the American people that Donald Trump is a con artist," Rubio told supporters in Florida on Tuesday night.

"In just five days, we have seen the impact it is having all across the country," he continued. "We are seeing in state after state -- he loves to talk about polls -- we are seeing in state after state his numbers coming down, our numbers going up."

That kind of evidence may embolden Republican opponents of Trump -- and a super PAC effort currently lining up against him staffed by establishment Republican operatives -- to test what damage a full-bore negative advertising assault on Trump's character and business record could wreak on the billionaire's polling.

But there is little precedent in this campaign for any effort by establishment figures to succeed in denting his hopes. It's even possible that efforts by the likes of Romney might do more to endear Trump with his loyal outsider base of voters than to harm him among traditional Republicans.