Ritter told other Democrats the job was taking a toll on his family and he could not be successful as a father and husband while running for governor, according to those briefed on the calls. Ritter has one school-age child living with him and wife Jeannie in the Governor's Residence. Three others are grown or in college but still nearby.
Sources said Ritter's office contacted key legislators asking them to be available for a news conference today at which Ritter will make his announcement following a morning meeting with his Cabinet.
Ritter's decision, first reported by a blog affiliated with Congressional Quarterly in Washington, D.C., was confirmed by The Denver Post and others.
Repeated calls for comment to Ritter's campaign, his office staff and communications director were not returned Tuesday night. The governor was continuing to make calls to other Democrats late Tuesday, informing them of the decision.
U.S. Sen. Mark Udall and U.S. Rep. Diana DeGette announced they would call a meeting of Democrats in the state's congressional delegation, along with Colorado Democratic Party chair Pat Waak, for 1 p.m. today to "discuss how to go forward as a party."
Ritter's departure from the race is the second time in a year that Democrats have dropped a New Year's bombshell. It was last year when Ritter announced he would appoint Michael Bennet rather than Denver Mayor John Hickenlooper to fill the U.S. Senate vacancy created by Ken Salazar's appointment as interior secretary.
Democrats scramble
Ritter's announcement today could set off a scramble among Democrats looking to succeed him in the race against Republican Scott McInnis, who leads Ritter in early polling.
Among the possibilities is Sala zar, who has run and won statewide races before in Colorado. But he has been in the Obama administration for just a year.
Salazar could not be reached for comment Tuesday night.
A Democratic source close to Salazar said the interior secretary, also a former Colorado attorney general, is "under tremendous pressure" from Colorado Democrats "to fill the void" left by Ritter's decision.
Despite Salazar's key role in energy and climate-change issues, the administration may be inclined to support a gubernatorial bid, the source said. The Western strategy used successfully by Democrats in the 2008 campaign looks very much in danger, and Colorado is key to that effort for Democrats and the White House in the future, the source said.
If Salazar chose not to return to Colorado, the field could be open for Hickenlooper, who three years ago contemplated a run against Ritter.
Other possibilities would include U.S. Rep. Ed Perlmutter of Denver's western suburbs, Lt. Gov. Barbara O'Brien, Rep. Jared Polis of Boulder, or former House Speaker Andrew Romanoff, now challenging Bennet for the Democratic nomination in the Senate race.
McInnis faces a GOP primary challenge from Evergreen businessman Dan Maes.
