Posted by John Chase and Kristen Mack at 10:44 a.m.; last updated at 4:23 p.m.

Cook County Sheriff Tom Dart, who is seeking re-election next week, said today he will not run for Chicago mayor next February.

Standing outside the jail he has overseen since 2007, Dart said he has struggled with the decision since Mayor Richard Daley announced last month that he would not seek another term.

"I couldn't do both," Dart said of running for mayor and being a father and husband. "It wasn't the appropriate thing for me just to take my time."

"For supporters of mine, I was being less than honest," he said.

Like several other politicians, the Democratic sheriff has had to juggle that calculation with the need to run for re-election on the Nov. 2 ballot. Dart supporters were laying the groundwork for a mayoral bid and he was ratcheting up his public appearances in recent weeks to keep his name out there while more certain mayoral candidates gained the spotlight.

"I have found it impossible for it to be compatible between running for mayor and being a father and husband," Dart said at the news conference.

"I'm disappointing people, but at the end of the day I have to look myself in the mirror," he said of those who wanted him to run for mayor.

Dart said no back channel overtures were made by other candidates to encourage him to get out of the race. "I haven't spoken to any other candidates at all," he said, with the exception of U.S. Rep. Luis Gutierrez calling him after the congressman announced he wasn't running.

Dart said he did not call any of the other candidates and said he has "no intention" of doing so.

Dart's announcement comes just days before he is up for re-election against Republican Frederick Collins. A former state representative from the South Side, Dart has strong ties to the 19th Ward organization, including the former sheriff, Michael Sheahan.

Dart is the latest in a lengthy list of big-name politicians to consider but then back away from a run for mayor. But former White House chief of staff Rahm Emanuel, former Chicago school board chief Gery Chico and city Clerk Miguel Del Valle are in so far.

In recent days, U.S. Reps. Jesse Jackson Jr., Luis Gutierrez and Mike Quigley have all ended their consideration of a mayoral bid, as have former Ald. Manny Flores and Cook County Commissioner Bridget Gainer.

Reactions started to roll in this afternoon following Dart's announcement.

Emanuel said Dart is a "good man. He's clearly invested in his job, this city and his family."



"The dynamics obviously change when someone of Tom Dart's quality and capacity gets out. That has an impact," Emanuel said, adding that he would leave the political interpretation to experts.



"You have an evaluation of what drives you, what motivates you personally and professionally. You gotta respect him," Emanuel said of any individual considering a run for public office.



"He took a gut check of that decision. Tom Dart does not get scared," out of a race, Emanuel said.



"Nobody is going to hand you this election but the voters," Emanuel said.



He said neither he nor anyone in his campaign talked to Dart about whether he would run. Said he called Dart this afternoon and left him a voice mail.

City Clerk Miguel del Valle, a mayoral candidate, issued a statement.

"I am grateful for his contributions to our great city and look forward to working hard to garner his support and endorsement," del Valle said.

Mayoral candidate Gery Chico, a longtime Daley troubleshooter, also issued a statement.

"Sheriff Dart has always put public service ahead of political ambition. I wish Tom well as he continues his good work to fight crime in Cook County. I have always believed that protecting our citizens is the number one priority of government. As I have in the past, I will seek Sheriff Dart's advice and counsel on keeping Chicago safe," Chico said.