Karzon, 19, beat Syrian Ruweida Attiyeh for the title of "Superstar", in a show that has been beamed into Arab homes over the past few months by a Lebanese satellite channel.
An Arabic version of the UK show Pop Idol, Superstar was an instant hit, as week upon week viewers were asked to vote for their favourite entertainer.
Thousands of contestants from all over the Arab world were eliminated in telephone, text message and internet voting to arrive at the final 12.
Lebanon's Melhem Zein, who made it to the top three slots, was eliminated from the race last week, leaving Karzon to face Attiyeh.
But before leaving the stage, Zein threw a bombshell when he asked viewers who had supported him to back Attiyeh.
"This show harms national values and... deviates future generations from... the more important and decisive causes"
The Islamic Action Front
His remarks fueled widespread rage in Jordan and triggered clashes outside Future TV's station in Beirut.
But with all that now history, Jordan's King Abdullah II was among the first well-wishers to congratulate Karzon on her victory late on Monday.
The monarch "pledged his full support for Karzon's music career" in a telephone call to the young singer minutes after the results were out.
However, not everyone was elated with the success of Karzon, whose victory earns her a contract with a major recording studio as well as cash and prize gifts.
Jordan's opposition Islamic Action Front (IAF) blasted Jordanians for giving all their attention to the show when they should be more concerned by events in Iraq and Palestine.
"This show harms national values and causes, distorts public perceptions, deviates future generations from their aspirations and the more important and decisive causes," the IAF said in a statement.
"We also urge the ulemas, opinion makers, intellectuals, writers and all sincere people to confront this dangerous phenomenon and deal with its destructive repercussions."