(Image Credit: ABC News)

As a former national security staffer for President George W. Bush, President Obama's nominee to be U.S. Ambassador to Iraq, Brett McGurk, was supposed to garner bipartisan support for his confirmation.

That support has suffered after emails of his wooing a female Wall Street Journal reporter - perhaps jokingly referencing favors of access and information - were leaked last weekend, Senate sources said. He later married the reporter.

The emails have alarmed many senators on the Foreign Relations Committee, which began McGurk's confirmation hearings this week, sources said. Senators want to question McGurk about suggestions in the emails, jokingly or otherwise, that he would give a reporter access to sensitive information and power if their relationship blossomed.

"Overnight, support for him as cratered," a Republican staffer on the committee said.

Sen. Jim Inhofe, R-Okla., has already canceled a meeting with McGurk because of this and another allegation, refusing to get together until the nominee answers questions about these emails and what they mean.

"There is concern about whether or not he did divulge information that he shouldn't have and whether or not his conduct represents a level of immaturity and inexperience that would bar him from taking on a very serious national security post in the middle of a very delicate situation in Iraq," Josh Rogin of Foreign Policy Magazine told ABC News.

Iraq remains a fragile ally of the United States, and the ambassador post is considered one of the most important for U.S. foreign policy in the Middle East. U.S. lawmakers will not be the only ones to question McGurk's fitness to serve. Iraqi officials, some of whom have already expressed concern about McGurk's nomination, will also likely raise eyebrows because of the scandal.

McGurk has so far refused to comment on a collection of racy emails he purportedly exchanged with reporter Gina Chon while both were working in Iraq in 2008. McGurk, who was married at the time, was serving as chief negotiator during the 2008 U.S.-Iraq security agreement talks. Chon was covering the negotiations for the Wall Street Journal. McGurk later divorced his wife and married Chon.

The blog Cryptome published the emails earlier this week, but McGurk, Chon and the State Department have refused to comment on the months-long string of messages, sent from McGurks official State Department email address. ABC News has confirmed the authenticity of the emails.

The emails are sexually explicit with references to masturbation. In one, Chon jokingly refers to reporters as vultures attacking sources, to which he replies, "If treated to many glasses of wine - you could be the chosen vulture."

McGurk also talks about bringing the reporter with him to dinner with a leading Iraqi politician. He ultimately does not, but later writes, "I had a very good day with the Iraqis … the best yet. Can't tell you about it of course. But you should definitely stay past Sunday."

Rogin of Foreign Policy Magazine says it's the appearance of a senior diplomat's granting access to a reporter based on sexual innuendo that has some senators concerned.

"Some of the emails indicate that McGurk and the Wall Street Journal reporter were exchanging information at the same time they were beginning their relationship," Rogin said. "That doesn't necessarily mean that there was impropriety, it creates the appearance of impropriety."

The Wall Street Journal issued a statement saying the paper "is looking into the matter." Chon had already requested a leave of absence from her current job as a reporter focused on money and investing, after McGurk was nominated for the ambassador post. The journal said she is scheduled to go on leave at the end of the summer.

The emails add to concerns Sen. John McCain, R-Ariz., and others on Capitol Hill have previously expressed about McGurk's nomination. He has no administrative experience running a large organization and has never been a foreign service officer, but would be running the largest U.S. embassy in the world.

There has also been criticism of his handling of U.S. troop withdrawal negotiations. Within Iraq, opposition political parties have expressed concern that McGurk is too close to President Nouri al-Maliki and will not be objective in a country already ripe with sectarian tension.

Rogin, who's covered the criticism of McGurk in Foreign Policy Magazine extensively, says the email scandal "adds to the narrative of a national security official operating in Iraq who may not have been holding himself up to the highest standards of conduct expected of a government official in a very sensitive position in a war zone."

Despite the controversy, a GOP Senate source said he wouldn't be surprised if McGurk is still confirmed. The Iraq ambassador post is a challenging and sensitive position and Republican senators fear that no other Obama nominee would be as palatable.

Although the process might be messy and will make both McGurk's friends and detractors on the Hill uncomfortable, the source says, as a Republican and former Bush White House national security staffer, McGurk has a good chance of surviving the scandal.