AUGUSTA — U.S. Sen. Olympia Snowe’s sudden decision to abandon her re-election bid is a political earthquake. Now come the obvious questions.

Why now? What happens next?

Only Snowe, who has served in Congress for nearly three decades, knows the answer to the first question. She has had many months to consider whether she would seek another six-year term in the U.S. Senate, the filibuster-prone chamber that often seems to best capture the impassable partisan divide.

Snowe has frequently bemoaned that rift. On Tuesday, in a press statement only her inner circle saw coming, she mentioned it again.

“Unfortunately, I do not realistically expect the partisanship of recent years in the Senate to change over the short term,” she said. 

But the question remains: When did this savvy veteran pol reach this determination? Snowe has already raised millions in campaign funds. She announced her candidacy months ago. In her statement Tuesday, she noted that she was well-prepared for a political battle. She is, she said, “a Spartan.”

In her statement, Snowe made repeated references to the partisan climate and the prevalence of “my way or the highway ideology.”

Pundits and national columnists lamented that she and other moderate lawmakers were “tacking right” to appease her party’s right wing and win re-election.

On Monday, in a column headlined “The Possum Republicans,” New York Times columnist David Brooks said moving away from the center was normal behavior for politicians facing re-election. However, Brooks added a caveat.

“Still, it is worth pointing out that this behavior is not entirely honorable,” he wrote. “It’s not honorable to adjust your true nature in order to win re-election. It’s not honorable to kowtow to the extremes so you can preserve your political career.”

Only Snowe knows whether she was uncomfortable courting the right flank of her party. However, it’s clear that she often embraced and worked hard to nurture her moderate image.

Her Democratic opponents often scoffed at her centrist reputation. Following one of her votes on the payroll tax extension, joining the GOP to block the appointment of President Barack Obama’s consumer protection czar Richard Cordray and other votes, her opponents felt Snowe’s appeasement of the right was more apparent than ever.

In the relentless world of Twitter and blog commentary, some speculated that something else factored into Snowe’s withdrawal from the race.

Was there more trouble with her husband John McKernan’s business, Education Management Corp., which is the subject of a multi-state lawsuit headed by the U.S. Department of Justice? Documents from the lawsuit suggest McKernan had mostly inoculated himself from the EDMC controversy. The couple has vigorously denied any wrongdoing.

However, Snowe’s political opponents suggested there was more to the story, citing the couple’s reported assets from EDMC, which in 2009 were valued at between $6 million and $25 million and divided among her and McKernan’s stock options and common stock holdings.

Only Snowe and her inner circle know whether EDMC played any role in her decision to withdraw.

She’s expected to discuss her departure from the campaign Friday when she returns to Maine.

For now, the speculation turns to the political horse race. Who will try to take her place?

For Republicans, Snowe’s decision leaves some tough decisions for the party. Republican Scott D’Amboise is already in the race; however, his support from the GOP establishment appears tepid.

D’Amboise, in a statement, said Tuesday that it would be difficult for other candidates to get on the ballot for the June primary.  

Snowe’s withdrawal leaves Republican candidates a little more than two weeks to gather 2,000 certified signatures by the March 15 deadline. The same goes for Democrats. 

The tight window narrows the potential field to two types of candidates: those who have up-and-running campaigns and those who have the financial resources to fire one up on short notice. 

Getting signatures from registered Republican voters will be tough, said former Republican lawmaker and gubernatorial candidate Peter Mills.

“The caucuses are over, so you can’t go the traditional way of getting signatures,” he said. “Snowe’s probably already got hers. You’d have to get a voting list at different locations and go door to door.”

The list of potential Republican candidates includes state Senate President Kevin Raye, R-Perry. He is campaigning against U.S. Rep. Mike Michaud, D-Maine, for the 2nd Congressional District Seat. Raye, a former senior staffer for Snowe, said Tuesday that he would carefully “weigh his plans for 2012.”

Pundits had considered Raye a real threat to unseat Michaud, given Raye’s championing of rural Maine during the legislative session. However, it’s unclear whether Raye’s legislative achievements, which included a bill adjusting school funding formulas to pipe more money to rural schools, would be a liability in a Senate race that includes the more urban 1st Congressional District. 

Other Republican possibilities include former gubernatorial candidate Steve Abbott, Secretary of State Charlie Summers and former gubernatorial candidate Peter Cianchette. 

The game has completely changed for Democrats, who have typically viewed contests against Snowe as an opportunity to increase the profile of challengers, not as winnable races.

“Maine is now a top pickup opportunity for Senate Democrats,” Democratic Senatorial Campaign Committee Executive Director Guy Cecil said in a prepared statement. “If there is one place in the country that is likely to reject the extreme, anti-middle-class, divisive Republican agenda, it is Maine.”

But who will run? Former Secretary of State Matt Dunlap is already in; so are state lawmakers Sen. Cynthia Dill, D-Cape Elizabeth, and Rep. Jon Hinck, D-Maine.

However, with Snowe out, the talk has shifted to established party superstars, Michaud and U.S. Rep. Chellie Pingree, D-Maine. 

Within hours of Snowe’s announcement, Michaud said he was “seriously considering entering the race.” Greg Olsen, his campaign manager, said the campaign would “catch its breath and survey the lay of the land” before making an announcement. 

Pingree, meanwhile, appeared less inclined to jump into the race. Some Democrats in Augusta believe her career in the House of Representatives is on the appropriate trajectory. There is also some question whether Pingree’s unabashed liberal policy positions would play well in the 2nd Congressional District, which she would have to win. 

Some have wondered whether former independent gubernatorial candidate and Snowe ally Eliot Cutler will jump in. He already has a political machine up and running in OneMaine. Ted O’Meara, Cutler’s former campaign manager, said Tuesday he would be surprised if the former aide to U.S. Sen. Edmund Muskie and a White House bureaucrat would want to return to Washington, D.C.

“I have no reason to believe he would want to go back,” O’Meara said. 

Other names have surfaced, but none was ready to come forward Tuesday night. Snowe’s announcement was that sudden, that unexpected. 

It will take time to sort out the implications which, depending on who jumps into the race, could reverberate into the other two congressional races and legislative contests.

Candidates will be chosen. Plans will be made. Republicans and Democrats will have only a few days to sort it all out.

In the meantime, the focus will shift back to the demure Snowe and her bombshell announcement. On Tuesday, it was the third-top story on NBC Nightly News.

In Maine, it could be the story of the year. 

smistler@sunjournal.com