New Jersey Democrats head to the polls Tuesday for a special primary election to determine just how huge of a landslide Newark Mayor Cory Booker walks away with.

Booker has led by seemingly insurmountable margins in the race to fill the seat vacated by the late Sen. Frank Lautenberg (D), who died in June. A Quinnipiac poll released last week showed Booker up by 37 points over his closest competitor in the primary. And in solid-blue New Jersey, that means Booker should have a pretty smooth glide to the Senate.

Yet Booker is the front-runner not necessarily because of his political accomplishments, but rather his remarkable ability to promote his public persona as a champion of the people. That, some fear, is exactly the problem with sending him to Congress.

In the world of politics, Booker is perhaps unrivaled in his use of social media to bolster his image. He has used his Twitter account — which boasts an incredible 1.4 million followers, nearly three times as many as New York City Mayor Michael Bloomberg's account — to engage in idle banter with constituents and earn himself favorable headlines.

He offered to dig out residents trapped during a 2010 blizzard — even personally delivering diapers to one stranded woman — rescued an allegedly abused dog, and responded, in timely fashion, to pothole complaints.

Away from Twitter, he once saved a neighbor from a burning building.

While Booker's constituents love him for those random acts of retail politics, the job of senator demands a focus on more deliberative matters. Saving puppies, though a nice gesture, is a far cry from haggling over a landmark immigration bill.

Here's TIME's Jay Newton-Small on that point:

Retail politics is a skill wasted in that stuffy chamber, where senators only have to go out and touch real people — er, shake hands with their constituents — once every six years. Senators don't fix potholes. Never mind flaming buildings — they rarely even kiss babies. Senators spend their days in meetings: with lobbyists, with interest groups, with other senators, with the administration, with fundraisers and with their leadership. They're inside operators.

In other words, Booker's frenetic energy and love of real-world interactions are far better suited for a big city like Newark. Or Iowa or New Hampshire, and the other stomping grounds of a presidential candidate, something the ambitious Booker likely aspires to be someday. [Time]

Booker's critics also argue that his actions as mayor don't bear out his progressive image. He has soaked up millions in donations from wealthy tech entrepreneurs and financial juggernauts, but Newark, they say, is hardly better off. All that glad-handing with moneyed elites has only fueled speculation that Booker has for some time been more interested in using the mayor's office as a springboard to higher office than in actually governing New Jersey's largest city.

Booker is "the worst sort of Democrat," says Salon's Alex Pareene, because he's essentially "an avatar of the wealthy elite, a camera-hog, and a political cipher who has never once proposed anything to address to the structural causes of the problems he claims to care so deeply about."

More from Pareene:

In many ways, Booker is perfectly suited for the United States Senate. He won't be expected to accomplish anything. He will have so many more opportunities to spend time with even more rich people with elite backgrounds and worldviews similar to his. He will have much more access to television studios and Sunday shows and cable news cameras.

He will, in short, be the worst kind of senator. The kind that has no power and no real desire to exercise power on behalf of the people the senator ostensibly represents, but the kind that always expresses opinions on television about whatever national issues people on television care about that day. [Salon]

A conservative PAC has already gone up with an ad accusing Booker of being just that: A cheerleading, do-nothing politician.

Should Booker win Tuesday and go on to win the general election, he would replace Sen. Jeff Chiesa, the Republican handpicked by Gov. Chris Christie to replace Lautenberg in the interim. In that respect, the simple act of his presumed election would benefit Democrats by giving them a bigger edge in the upper chamber.

But beyond that, Booker will have to prove that he can rise to a different kind of challenge — indeed, his future in politics may depend on it.