Mayor Bill de Blasio's poll numbers are taking a dive. He's suffered from weeks of bad headlines over investigations into his fundraising, and he's facing criticism for attempting to hide from the public emails he exchanged with outside advisors, a story first reported by NY1. NY1's Grace Rauh filed the following report.

Mayor Bill de Blasio looks increasingly vulnerable. His poll numbers have hit a new low.

Just 41 percent of city voters approve of the job the mayor's doing and 52 percent disapprove, according to a new Quinnipiac University poll.

A NY1-Baruch College conducted in April as news was breaking about the federal investigation into the mayor's fundraising showed de Blasio's approval rating seven points higher.

The Quinnipiac poll, out Tuesday, shows potential challengers may have a shot at beating de Blasio next year.

In a hypothetical match-up against City Comptroller Scott Stringer, running as an independent, de Blasio would get 37 percent to Stringer's 36 percent. It's close with Brooklyn Borough President Eric Adams as well, with de Blasio at 35 percent and Adams, running as an independent, just behind him with 34 percent.

A spokeswoman for the mayor said polls are unreliable and added that the mayor will be judged by his results.

Stringer, meanwhile, knocked de Blasio for insisting that five of the mayor's outside advisors are actually agents of the city and not subject to the open records law.

"I am very concerned that people are being designated as secret special agents at a time when we should be having the most open, transparent government," Stringer said.

Emails between the mayor and people outside government are supposed to be made public upon request.

De Blasio on Tuesday addressed a diverse group of people looking to do business with the city.

The mayor has been keeping a low profile since revealing his five agents of the city. He has not taken any questions from reporters, and he left town last weekend to spend time with his brother in Seattle.

After speaking at the city business event, the mayor made a beeline for the service elevator as reporters trailed him.