New Jersey Attorney General Peter G. Verniero has enjoyed a stellar rise in state politics during his 15 years as a lawyer, but an ill-timed nomination to the Garden State’s high court may bring an end to his ascension.

After a stint at two New Jersey law firms, Mr. Verniero followed his benefactor, Republican Governor Christine Todd Whitman, to the state capital, where she appointed him attorney general. Then, in February, at the age of 39, he was nominated to the state’s Supreme Court. But in the three months since, increasing concern about his inexperience and about the explosive issue of racial profiling by New Jersey state troopers has raised strong doubts about whether he has enough support to be approved.