Chicago’s Hyde Park is the home of the 13th District of the Illinois State Senate, which Barack Obama represented between 1996 and 2004. It is a quiet, tight-knit community that houses the University of Chicago as well.

It was during his Hyde Park years that Mr. Obama crafted his lofty rhetorical style. He endeared himself to the local constituency, which now, as he inches closer to securing the Democratic nomination for president, waits with bated breath and great pride to see if, indeed, yes he can.

But Mr. Obama was an easy sell in Hyde Park, a staunchly Democratic district. He’s a fresh face with the same old Democratic message albeit delivering it in a more appealing way. He’s never had anyone to challenge him ideologically. In all three of his elections for his State Senate seat in 1996, 1998, and 2002, he was either officially or de facto unopposed. He acquired his current Senate seat, the only other elected office he has held, after dispensing with the last minute, half-hearted effort of gadfly Republican Alan Keyes.

Mr. Obama has always run in Democratic territory, and therefore has rarely had to oppose a Republican candidate or put up a strong fight against one. So what makes the Democratic party think he could take one on in the presidential race?

The junior senator appealed to Hyde Parkers not only because of his persona but also because of the policies he backed. When he represented Hyde Park he worked on an agenda of issues dear to Democrats, from the minimum wage to campaign finance to more money for schools.

Mr. Obama communicated these policy positions to his constituents by writing relatively banal articles in the local paper, the Hyde Park Herald. Here he explained, for instance, that raising the minimum wage would be a way to “give a much-needed boost to thousands of low-income families without having a negative impact on the economy.”

He had the luxury of politics without the politics, which enabled him to translate quotidian legislative work like easing the pain of high energy costs into moving campaign rhetoric like transitioning “from a politics of protest to a politics of progress.”

Like Johnny Carson, it was all in the delivery.

Predictably, the Herald, speaking on behalf of the community, is “holding its breath” watching Mr. Obama’s candidacy gain steam. And, everybody I know here — both at the University of Chicago and in the Hyde Park community — is pulling for Mr. Obama.

The Obama they are supporting is an idealized candidate unsullied by political competition. If Mr. Obama is to succeed, this trend will have to change because when it comes to voters who aren’t united behind the policies he advocates his “politics of unity” will be meaningless.

The junior senator has been in two close elections other than the current Democratic presidential primary, but they were also Democratic primaries. As when he represented Hyde Park, these intra-party competitions played directly to his strength as an inspiring communicator. Mr. Obama neither needed to nor was motivated to highlight philosophical, ideological, and political differences.

When he ran against the incumbent Democratic congressman, Bobby Rush, for the 1st District seat, which also includes Hyde Park, in 2000, he relied upon the type of speech that has become quite familiar to followers of his current campaign.

His critique of his competition emphasized Mr. Rush’s “inability to shape that proactive agenda that voters have been looking for.” Mr. Obama had nothing concrete to say about Mr. Rush or his policies. In spite of an endorsement from the Chicago Tribune Mr. Obama lost to Rush by a 2-1 margin.

In 2004 Mr. Obama won a tough primary battle for the Democratic nomination for the Senate seat that he then won in a landslide against Alan Keyes.

Competing exclusively against Democrats, he relied on the same rhetoric yet again: when speaking to a group of young professionals at a fundraiser, he characterized himself as “your instrument potentially to create a new kind of politics in this town.”

Mr. Obama may be the most pleasant politician America has had in a long time, but, then again, it is easy to unite when there is no divide. And it is easy to move forward when there’s no question about how to do it.

It would be almost a shame if Mr. Obama were sullied by an actual ideological and political challenge next fall. Especially if it got in the way of the “politics of progress.”

Mr. Fleisher is a graduate student of political science at the University of Chicago and lives in Hyde Park.