As Donald Trump’s campaign prepared for the most important speech of his brief but meteoric political career – one it hopes will not only propel him to the White House but unite a divided Republican Party – his November opponent was hunkered down just days before her coming-out party begins to find the right fit for the Democratic ticket.

In Cleveland, the Republican Party standard-bearer was putting the finishing touches on his nomination acceptance speech. Trump’s address is set to cap a dramatic convention week marked by powerful displays of party unity but also tensions, flaring most recently when Ted Cruz withheld his endorsement Wednesday night.

But those tensions could pale in comparison to those on the Democratic side, where Hillary Clinton is trying to strike the right balance with the base as she weighs her running mate options, after a rigorous primary battle against liberal Vermont Sen. Bernie Sanders, who only came around to endorse Clinton days ago. 

While Cruz's controversy was fading, Clinton might have to fret about Sanders' address next week to his own delegates in Philadelphia -- whose allegiance may still be up in the air. 

The plot thickened in the Democratic veepstakes Thursday, as a source familiar with the vice presidential search process told Fox News that Clinton met last Friday with New Jersey Sen. Cory Booker at her Washington home. 

Asked about the process during a pro-Clinton press conference in Cleveland, Booker said: “I’m here to talk about the convention ... I know the Clinton campaign is in the midst of deciding. I’m very happy to be where I am.” 

It was already known that Clinton had met with several other prospects, including Massachusetts Sen. Elizabeth Warren, Colorado Gov. John Hickenlooper, Labor Secretary Tom Perez and Housing Secretary Julian Castro – though some problems have since surfaced with that list.

Time is quickly running out for Clinton, considering the convention, which starts Monday in Philadelphia, is where the presidential and vice-presidential candidates are formally nominated.

She reportedly said she would make a decision this Friday.

Another curveball came in the form of an apparently errant and mistaken report that Clinton was considering former Florida Gov. Charlie Crist, a Republican turned Democrat. But that report was pulled back, and Crist downplayed the talk.

He told The Tampa Bay Times Clinton was coming to Tampa and they would meet but knew of no plans to consider him for the ticket.

"Not that I'm aware of," he told the newspaper.

The eleventh-hour speculation comes amid reports that Clinton was narrowing her selections down to Virginia Sen. Tim Kaine and Agriculture Secretary Tom Vilsack.

Booker, though, was among the first prominent Democratic lawmakers to endorse Clinton and has been a strong advocate for her campaign since essentially the start of the election cycle.

Clinton does extremely well with African-American voters, based on recent and exit primary polls. But Booker, who is black, could help her expand her outreach among minority voters in her general election race against Trump.

Both Castro and Perez, meanwhile, have faced some turbulence over the last week.

Castro was just cited for violating federal law when he touted Clinton’s candidacy in an April news interview. 

The Wall Street Journal then published a potentially problematic report on Perez, who regularly retells the story of grandfather Rafael Brache being forced to flee the Dominican Republic for opposing the dictatorship of Rafael Trujillo. Perez has praised his grandfather as being “on the right side of history.”

What Perez didn't offer up as often is that his grandfather was one of the dictator’s champions during the first five years of his three-decade rule. 

The Wall Street Journal said Brache also held a string of high-level offices in the Trujillo regime, including being ambassador to the U.S. Brache reportedly “expressed great optimism” for the regime as late as 1935 when political assassinations had been well documented. 

Kaine, long rumored to be on Clinton's short-list, still seems to be the leading contender. The former Virginia governor, who represents a key battleground state, is considered a safe choice for Clinton, someone who could help her appeal to moderates who have been turned off by Trump's rhetoric.

However, Vilsack, a former Iowa governor who is a longtime friend of the Clintons, is being described as a "strong" second choice. 

Fox News’ Mike Emanuel and Jennifer Griffin contributed to this report.