Originally Published: 15 NOV 22 05:00 ET

Updated: 15 NOV 22 09:15 ET

By Gabby Orr and Steve Contorno, CNN

(CNN) -- Should Donald Trump announce his third presidential bid on Tuesday, as is widely expected, he will begin the next phase of his political career under siege.

Seven years ago, the New York businessman entered the political fray on defense, working vigorously to cast himself as a serious contender for the Republican presidential nomination to the incredulity of veteran political operatives and his primary opponents. This time, Trump takes the plunge as the party's indisputable frontrunner, but once again, he finds himself in a defensive crouch.

On the brink of a campaign launch that elicits both enthusiasm and dread from different corners of his own party, Trump's quest to return to the Oval Office could face untold obstacles in the months to come, even with his loyal base firmly intact. He has spent the days since the midterm elections fending off criticism from fellow Republicans over his ill-fated involvement in key contests, furiously lashing out at two GOP heavyweights who could complicate his path to the White House if they mount their own presidential campaigns, and fretting that he or associates could soon be indicted by federal investigators in two separate Justice Department probes.

Aides say Trump is hoping his early entry into the 2024 presidential primary will reframe the conversation away from Republican failures and inject a fresh dose of enthusiasm into a demoralized party amid GOP failures to capture Senate control and win a sizable House majority. Though the former president has been touting his 200-plus victories on Election Night, many of the Trump-endorsed Republicans who prevailed last Tuesday ran uncontested or were widely expected to win their contests, while several Senate candidates he endorsed in highly prized races failed to dethrone their Democratic opponents or flip open seats into the GOP's column.

Mehmet Oz, Adam Laxalt and Blake Masters, three Republican Senate candidates who earned Trump's support in their primaries, respectively lost to Democratic opponents in Pennsylvania, Nevada and Arizona. Meanwhile, Herschel Walker, a longtime Trump friend challenging Democratic Sen. Raphael Warnock, is headed to a December runoff after both failed to reach 50% support in Georgia.

On Saturday, CNN projected that Democrats will retain control of the Senate in the 118th Congress, an outcome that has fractured Republicans and left the party on tenterhooks as Trump readies his "big announcement."

Next targets

Trump, who in the immediate aftermath of the midterms conceded that his party had suffered a "somewhat disappointing" outcome, has already moved on, settings his sights on winning a second term in Washington and attacking two GOP governors who could challenge his status as the party's anchor in the months to come, Ron DeSantis of Florida and Glenn Youngkin of Virginia.

"I Endorsed him, did a very big Trump Rally for him telephonically, got MAGA to Vote for him -- or he couldn't have come close to winning," Trump said of Youngkin in a Truth Social post last week.

Three sources familiar with the matter said the former president believed Youngkin was supportive of comments his lieutenant governor, Winsome Earle-Sears, made during a Fox Business appearance last week. She told the network she would not support Trump if he runs for president a third time.

Responding to repeated questions about Trump's impending 2024 announcement, Earle-Sears said, "A true leader understands when they have become a liability. A true leader understands that it's time to step off the stage, and the voters have given us that very clear message."

Sears later declined to tell The Washington Post whether Youngkin knew prior to the interview that she planned to split from Trump, a detail that caught the former president's attention, according to one of his aides.

"If Glenn Youngkin decides to run for president, that's his choice. But Team Trump will certainly mount a massive effort to win the Virginia delegates going to Milwaukee that is going to embarrass Youngkin," said John Fredericks, a Virginia-based conservative radio host who chaired Trump's campaigns in the state in 2016 and 2020.

The former president's criticism of Youngkin, whose 2021 gubernatorial bid he endorsed against former Democratic governor Terry McAuliffe, came on the heels of a spate of insults Trump launched against DeSantis, the popular Florida governor who has refused to rule out a 2024 campaign against the former president and increasingly appears to be laying the groundwork for one. In the span of one week, Trump went from introducing a disparaging new nickname for the Florida governor ("DeSanctimonious") to heeding requests from Republicans to pare back his criticism of DeSantis in the home stretch before Election Day, to blasting out a scathing statement on the heels of DeSantis' reelection, calling him "an average Republican governor."

DeSantis allies said they do not expect the Florida governor to engage at all with Trump's bashing for as long as he can avoid it. In two press conferences related to Hurricane Nicole that DeSantis held after winning reelection by a 19-point margin, he did not mention the overall midterm results or take any questions. Notably, he has also avoided taking a victory lap on Fox News, which would undoubtedly inquire about Trump and 2024, after appearing frequently on the network while campaigning for reelection.

"Trump rants for a couple of months. DeSantis throws some red meat during [Florida's next legislative session] and then we have a primary around May," said one DeSantis ally, describing his current posture

Asked how long the governor can go without acknowledging Trump's attacks, a second DeSantis ally responded simply, "A long time."

Trump's bitter criticism of Youngkin and DeSantis, two rising Republican celebrities, was a stark reminder of the scathing brand of politics he brings to the campaign trail, without regard for how it might impact his own party. His first use of "DeSanctimonious" came just days before the Florida governor appeared on the ballot in his bid for reelection. And much to the chagrin of top Republicans, including some of Trump's closest allies on Capitol Hill, his Tuesday announcement comes as the party looks to prevent Senate Democrats from securing a 51-seat majority through the Georgia runoff.

"I know there's a lot of criticism and people saying, 'Just focus on Georgia,' but he figures there's no point in waiting. If Herschel loses, he'll be blamed for distracting from the runoff but if he wins, he doesn't believe he will get any credit for energizing the base," said a current Trump adviser.

Some of Trump's closest allies said Republicans should brace for a significant escalation in his attacks on rumored GOP challengers once he is a declared presidential contender, meaning he could ramp up his criticism of DeSantis, Youngkin or others while the party is fighting for Walker's survival in Georgia.

"Nobody should be surprised. This is how Trump does primaries," said Michael Caputo, a former Trump administration official who remains close to the former president. "The question you have to ask is whether this format can work for him again."

Of course, Trump has not been in a hotly contested primary since 2016, when he unleashed broadsides against more than a dozen-plus opponents with fury and vitriol that shocked some Republican observers but delighted a segment of the Republican primary electorate that would later evolve into his loyal base. Few Trump allies expect him to behave any differently in the months to come. Even if he remains the only declared candidate until others enter the fray next year, he will continue his preemptive blitz against perceived challengers.

"Donald Trump will make sure every Republican candidate is well-vetted," said a senior Trump aide.

"No one's going to get a free pass. It's going to be brutal," added the Trump adviser.

Other obstacles

The likelihood that Trump will face primary challengers may be the least of his concerns at this juncture.

While the former president maintains significant support from grassroots Republicans, some of the party's largest donors have been meeting with other potential presidential hopefuls and signaling they may be interested in bankrolling alternative candidates. It's a concern Trump allies are confronting head on as they privately explore ways to make the monstrous pile of cash he has raised since leaving office available to him as a presidential candidate. Billionaire Ken Griffin, who gave nearly $60 million to federal Republican candidates and campaigns in the 2022 cycle, told Politico in an interview last week that he would support DeSantis if the Florida governor tosses his hat into the ring for the 2024 GOP nod. Two other Republican donors who gave to Trump in 2016 and 2020 and requested anonymity for fear of retribution told CNN that they, too, were waiting to see what DeSantis decides to do, while one of them said they would also be willing to support former Vice President Mike Pence should he challenge his former boss.

"One of our biggest challenges will be the fundraising component but I do think [Trump] has proved that he doesn't need deep-pocketed donors, per se," said a person close to Trump, noting the enduring strength of his small-dollar operation.

Trump will also have to convince Republicans that he would be an asset at the top of the ballot in 2024 as opposed to an albatross for vulnerable candidates in tight races. That task comes amid a fraught intraparty debate over the GOP's bruising midterm outcome, with some Republicans claiming Trump's involvement -- including an eleventh-hour 2024 campaign tease at a rally on the eve of Election Day -- did more to hurt the party than help. Others have blamed party leaders for failing to articulate clear policy priorities, pointed to the party's money gap against Democrats in key races, or lamented the bickering that unfolded all cycle between two of the party's biggest campaign committees led by Florida Sen. Rick Scott and allies of Senate Minority Leader Mitch McConnell.

Some Trump allies said the donor challenges, midterm outcome and questions about his stature has left a dearth of seasoned campaign operatives willing to join his next campaign. Though the president has told allies he wants to keep his operation lean, much like his 2016 presidential campaign, some have privately questioned whether it's out of preference or due to recruitment troubles. CNN has previously reported that Trump's likely campaign is expected to be helmed by three current advisers -- Susie Wiles, Chris LaCivita and Brian Jack -- with assistance from a group of additional aides and advisers with whom the former president is already familiar. Overall, his 2024 apparatus is expected to dwarf in comparison to his reelection campaign two years ago, multiple sources said.

Either way, as Trump works to find his footing on the verge of a presidential campaign that could coast to the party's nominating convention or encounter any number of unforeseen troubles, allies who have stuck by his side said they are ready for battle one last time.

"Our team is accustomed to fighting tooth and nail. Team Trump is going to fight for the nomination," said Fredericks.