Those pondering runs include former gubernatorial candidate and Ambassador Peter Cianchette, ex-state House GOP Leader Josh Tardy, University of Maine Athletic Director Steve Abbott, state Treasurer Bruce Poliquin, Maine Secretary of State Charlie Summers, businessman Les Otten, former state Sen. Peter Mills, state Senate President Kevin Raye and state Attorney General Bill Schneider.
Scott D'Amboise is a long-shot candidate already running for the GOP nomination, but state and national Republicans are downplaying his candidacy.
Adding to the chaos, former Gov. Angus King (I) told Roll Call that he is "actively considering" running for the seat. In the past, King has done well in state polls in favorability ratings and name recognition.
King gave no indication as to which party he might caucus with if he ran and won the seat.
Another Independent considering a run is former gubernatorial candidate Eliot Cutler. Cutler has received calls urging him to run but remains undecided, according to Ted O'Meara, an operative who has worked for both him and Snowe.
O'Meara also said Cutler will likely not run if King jumps in. Cutler nearly beat Gov. Paul LePage (R) in the three-way 2010 gubernatorial race.
A candidate unaffiliated with a major party will have until June 12 to gather 4,000 signatures to qualify for the general election ballot. Because of the pushed-back filing deadline, there is much less urgency among the Independents.
A King or Cutler campaign could throw off the traditional partisan calculations that are made in a Senate race. Independents have a history of winning in the state. Democrats and Republicans are reluctant to discuss the effect that an Independent campaign could have on the way they plot their strategies.
O'Meara said that Cutler and King are unique personalities and that Maine's embrace of Independents does not extend to the possible open House races.
Michaud already had a competitive race on his hands against Raye, the state Senate president who is now considering a Senate run.
"We have a pretty good farm team," Webster said. Both he and national Republicans insist that if Raye opts to run for Senate, they have ready House candidates.
Webster also said he was flummoxed that the Democratic Party would leave "both flanks exposed" with the possibility of two open House seats.
Michaud's 2nd district is much more at risk than the 1st, and operatives from both parties agree that should he run for Senate, the seat will be much harder for Democrats to hold.
Vice President Joe Biden waits to conduct a mock swearing-in ceremony with Sen. Brian Schatz, D-Hawaii, in the Capitol's Old Senate Chamber, December 2, 2014. Schatz was sworn in to serve the remainder of his term since he was appointed to the seat after Sen. Daniel Inouye, D-Hawaii, passed away.