TRENTON, N.J. - (AP) -- One of Gov. Chris Christie's top aides is scheduled to answer questions this week from lawmakers who are investigating traffic jams last year near the George Washington Bridge even as Christie tries to put any hint of scandal behind him.
Regina Egea is to appear Thursday before the joint legislative task force. Lawmakers are expected to grill her on what she knew and when about the traffic jams and the relationship between the governor's office and the Port Authority of New York and New Jersey, which runs the bridge.
On the day Egea is to testify, Christie is scheduled to be in Iowa -- the state of the first presidential caucuses -- campaigning with GOP Gov. Terry Branstad and attending other events. The possible 2016 Republican presidential contender recently appeared on "The Tonight Show" with Jimmy Fallon and has been working to maintain his persona as a national Republican leader, which took a hit after the scandal broke.
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A WMUR Granite State Poll released last week of likely voters in the early New Hampshire Republican presidential primary found that Christie is both the top choice of voters there and the one most often picked by voters when asked who they would absolutely not vote for.
Christie had the support of 19 percent of the voters, 10 points higher than a poll taken in January when the bridge investigation was making daily headlines.
Christie has derided the legislative hearings, saying nothing new has been revealed despite the hours spent questioning his staff on the lane closures near Fort Lee.
But the other entities investigating the matter have not let Christie or his aides off the hook yet.
Egea is Christie's pick to become his next chief of staff, but she hasn't taken that spot yet, largely as a result of fallout from the traffic jams. Christie wants to move Kevin O'Dowd, who currently holds that position, to state attorney general but hasn't formally nominated him yet.
Last fall, Egea was in charge of overseeing for Christie independent and party-independent public authorities, including the Port Authority.
Documents previously released by the Democrat-led joint committee have pointed to Egea's involvement in the aftermath of the September lane closures.
On Sept. 13, Port Authority Executive Director Patrick Foye, an appointee of New York Gov. Andrew Cuomo, sent an angry email ordering the lanes reopened. "I believe this hasty and ill-advised decision violates federal law and the law of both states," he wrote.
Hours later, the deputy director of the Port Authority, Christie appointee Bill Baroni, forwarded a copy to Egea.
In November, Baroni testified before an Assembly committee about the lane closures, defending them as part of a legitimate traffic study -- a position that has since been discredited. Lawmakers later released documents that showed Egea helped edit Baroni's statement to the committee.
State Sen. Loretta Weinberg, co-chairwoman of the investigative committee, said she expects questions on both those areas.
"A key question" about the Port Authority, she said, "is how closely they are and should be related to either of the governors' offices."
Egea's lawyer, Michael Martinez, did not return a call from The Associated Press seeking comment.
Egea was one of 13 people on a list made by the legislative committee on whom it could subpoena.
So far, she is the only one who has been ordered to appear before lawmakers, who canceled two meetings scheduled for July.
Weinberg, a Democrat, said federal prosecutors have asked the committee's lawyer to hold off on some of the public interviews. The federal government is also investigating the lane closures.
The committee's list of possible witnesses, which was obtained by The Associated Press and other media outlets, includes Fort Lee Mayor Mark Sokolich and other Port Authority and Christie administration officials.
Weinberg said she hopes her committee can publish a report on its findings by early fall. She said besides explaining what happened last September, she also wants to offer possible reforms for the Port Authority.
It is not clear when the criminal investigation may wrap up or whether any charges could result.