– NBCUniversal Chief Executive Steve Burke, who acknowledges being a bit of a taskmaster, is in unfamiliar territory.

He took over the top job at a time when NBC Entertainment was hemorrhaging $600 million a year. Now the network is poised to end the current prime-time season on top among coveted 18- to 49-year-olds — the first time in 10 years that it will finish in first place in the ratings war.

NBC’s broadcast of the Olympics from Russia in February unfolded without a hitch and made money. The International Olympics Committee even handed NBCUniversal the U.S. broadcast rights to the Games for 18 more years.

And the most pleasant surprise was Burke’s high-stakes transition at “The Tonight Show,” with Jimmy Fallon replacing Jay Leno, and a relocation of the show to New York from Burbank. The switch worked better than anyone had anticipated.

“It has been an incredible few months — we are firing on all cylinders,” Burke said to NBCUniversal’s nearly 30,000 employees during a town-hall meeting.

The turnaround comes at the perfect time. The television networks this month are beginning to sell their commercial time for the upcoming season in the annual advertising auction known as the upfront market. NBC hopes that its newfound edge will help it grab ad dollars away from ABC, CBS, Fox and other competitors.

NBC’s prime-time spots had been selling at a discount to the rates at CBS, Fox and ABC, which enabled the other networks to collect $500 million to nearly $1 billion more a year in revenue. Burke is determined that NBC will make strides in closing the revenue gap during this ad market.

In his three years as CEO, Burke has earned a reputation among his underlings for pointing out the company’s shortcomings. A couple of Decembers ago, Burke displayed a Christmas tree decorated with red, yellow and green during a companywide broadcast of one of his talks. Green was good and red represented the disappointments, such as failed TV shows and movie box-office bombs. The tree was awash in red.

Emphasizing the importance of results has been a key ingredient of Burke’s plan to transform NBCUniversal and its corporate culture. He started when Comcast Corp. took over the entertainment company in January 2011.

Burke has installed new leaders at NBC. Companywide, only four senior executives are holdovers from the previous regime. “Historically NBCUniversal had brilliant people, but some of them didn’t do a very good job of working together,” Burke said. “Now we have people who are working well together.”