Mayor Bill de Blaisio’s approval rating reached a 17-month high in the aftermath of his handling of last month’s bombing in Chelsea, according to a recent poll.

Forty percent of registered New York City voters who participated in the poll feel de Blasio is doing an “excellent” or “good” job as mayor, his best rating since May 2015, NBC 4 New York reported.

"New Yorkers give the mayor his top grade for his handling of the recent bombing incident in Chelsea," Lee Miringoff, the director of The Marist College Institute for Public Opinion, said in a news release. Marist conducted the poll for NBC 4 and the Wall Street Journal.

Additional good news for the mayor is that half of the polled voters say de Blasio deserves to be re-elected – an increase of eight percentage points from the previous poll. De Blasio now hold a 20-point lead over any potential candidate in the Democratic Party primary.

Of the options offered to those polled about the primary, 42 percent support de Blasio. Twenty-two percent responded that they were “undecided,” followed by 12 percent for former City Council Speaker Christine Quinn, 9 percent for city Comptroller Scott Stringer and Bronx Borough President Ruben Diaz Jr. and 7 percent for state Rep. Hakeem Jeffries.

Marist surveyed 1,094 adults, of whom 799 were registered voters. The margin of error was 3.5 percentage points.