WASHINGTON -- This is one scenario that no one foresaw six months ago: Jeb Bush entering the presidential race as an underdog. With his name recognition, solid resume as a conservative two-term governor of a key swing state and intimidating access to Wall Street donors, what could keep him out of the lead? But the latest poll numbers show that Bush has lost ground to Scott Walker and Marco Rubio. His positions on immigration and education, his underwhelming performance on the stump, and lingering “Bush fatigue” have cost him more than observers expected. He's still a top-tier candidate, but he's not the overwhelming favorite anymore.

Being the guy in second – or even seventh –  place has its pluses. You're not in the bull's-eye, so you can spend your time raising money instead of fending off attacks. And it builds a nice narrative: Bush enters the race down in the polls, stands firm on his (sometimes) controversial positions and persuades the GOP primary electorate to support him. In other words, he'll be perceived as having earned the nomination, not merely having it handed to him like, say, Hillary Clinton.

That's assuming he does actually win the nomination. He is leading in one crucial competition: raising money. Bush announced in December that he was considering running for president and launched a super PAC, “Right To Rise.” His super PAC set a goal of $500 million, which would shatter previous fundraising records. It now seems unlikely that he'll clear $100 million -- so even his well-filled war chest is seen as something of a disappointment.

Instead of greeting voters at a Pizza Ranch in Iowa or the local GOP meetings in New Hampshire, Bush has been holding high-dollar fundraisers to bulk up the super PAC -- which will eventually spend the money for campaign advertisements. Critics have noted that even though he hadn't declared as a candidate, he was acting like one while raising money and therefore possibly crossing the legal line on coordinating with the political action committee.

But money can’t buy love, even if it can buy hordes of television, radio and Internet ads, and Bush will have to convince a primary electorate with an abundance of options to side with him. After two election cycles in which the GOP nominated moderates only to see them lose, conservative voters see right-wingers like Rubio, Walker and Ted Cruz, who are more in line with their views and values, as reasonable choices. Walker in particular seems increasingly formidable.

"[Jeb] is behind because he is a moderate, and moderates are less exciting than people who slay or attack demons,” said Samuel Popkin, a political science professor and author of “The Candidate: What It Takes To Win  -- And Hold -- The White House.” “The [Republican] party is in too optimistic a mood to settle for 'winnable' over 'ideal' yet. He has to get into the ring and show that they cannot deliver and that he can."

As his poll numbers sank, Bush became a somewhat smaller target. "The person that seems to be leading at any particular point will draw most of the criticism from both the rest of the field as well as the other side," said  Tim Hagel, political science professor at the University of Iowa. "That was one of the things that contributed to the 'leader of the week' format that seemed to grip the Republican field in 2011. Aside from their other problems, as each candidate rose to the top, he or she became the focus of those supporting [Mitt] Romney and the other candidates. They often couldn't stand the scrutiny and fell back."

Bush has plenty of time to catch up. Candidates who have already announced got a quick bump in the polls, and Bush's is yet to come. The first primary is months away, and polls will shift a lot in the interim. "Once he engages fully, we are likely to see him make a stronger case to conservatives who are skeptical of him at present," Hagel said. "It's unclear whether he can win them over, but if he can mitigate their concerns on his positions regarding immigration and Common Core, he should be in fairly good shape."

Unlike Hillary Clinton in 2008, who let problems fester for months, Bush has moved swiftly to address weaknesses with his staff. He announced this month that Republican campaign veteran Danny Diaz would be his campaign manager rather than David Kochel, who worked for Mitt Romney in 2012 and was recruited by Bush in January. The shake-up made it clear that there's some nervousness in the Bush camp about his early showing.

The candidate himself is part of the problem. He doesn't seem to have done his homework -- for example, failing to prepare an answer to the extremely predictable question of whether, knowing what we know now, he wouldhave invaded Iraq as his brother did. He needs a crisp reply on that issue, as well as a way to distance himself from George W. Bush's claim to have understood the "soul" of Russian leader Vladimir Putin and his expectation that the U.S. would have "a very constructive relationship" with him.    

But Jeb Bush doesn't need to worry about the problem that most underdogs face: getting the press and the public to pay attention. He has the benefit of a great deal of political experience, having gone through his father's and brother's campaigns.  

“The GOP establishment and most of the media still believe Bush is the front-runner,” said Larry Sabato, a political science professor at the University of Virginia. “Why? Because we're used to the well-funded Republican establishment choice winning after a few bumps." 

With his money and family network, “Jeb Bush looks like a Sequoia in the forest," Sabato said. "But the clear lack of activist enthusiasm for him could prove the tree is hollow and can be felled,” he warned.