AUGUSTA – Democratic, Republican and Green party leaders are hustling to find replacements for 40 legislative candidates who have dropped out of the running this year, mostly because of competing personal commitments.

The major parties have until July 26 to fill the vacancies, which were announced with the passing of a deadline Monday.

Among the last-minute reconsiderations was Sen. Edward M. Youngblood, R-Brewer, who cited family obligations as his reason not to seek a third term.

Youngblood’s decision prompted three-term state Rep. Richard Rosen, R-Bucksport, to end his re-election bid and, instead, become a replacement candidate for Youngblood’s seat. District 31 encompasses communities east of the Penobscot River in Penobscot and Hancock counties.

If selected by Republicans in the district, Rosen will be opposed on the November ballot by Earl Sherwood, a Brewer Democrat.

Adding to the domino effect triggered by Youngblood’s withdrawal, Kim Rosen, wife of the aspiring Senate candidate, has decided to run for her husband’s House District 40 seat. It comprises all of Orrington and Bucksport.

Richard Rosen said Tuesday he was “anxious to get started” with his campaign. He added that his wife had become well-acquainted with the House district’s constituent issues “just by answering the phone.”

“We plan to present ourselves at the Republican caucus and hope that they choose to nominate us,” he said.

Other withdrawals in northern and eastern Maine legislative districts include:

. State Rep. Jonathan Thomas, an Orono Democrat whose District 19 seat represents the heart of the University of Maine community. Emily Ann Cain of Orono has been selected by the town’s Democratic committee to replace Thomas, who plans to pursue a graduate degree. The District 19 Republican candidate, Peter Fullerton of Orono, withdrew from the race on June 30, leaving local GOP leaders to find a substitute.

. Former state Rep. Catharine “Kay” Lebowitz of Bangor announced Monday she would not be the Republican nominee for the House District 15 seat in Bangor.

Others who have reconsidered:

. David Sturgeon, the Democratic nominee for House District 20, which encompasses Holden, Eddington, Clifton, Dedham and Bradley.

. Aymie Elizabeth Walshe, the Democratic nominee for House District 25, which encompasses a handful of towns in the Newport area.

. Josephine S. Cooper, the Democratic nominee for House District 34, which encompasses several Hancock County communities stretching from Lamoine to Gouldsboro.

. Merle F. Cousins Jr., the Republican nominee for House District 35, which encompasses Bar Harbor, Southwest Harbor, the Cranberry Isles and portions of Mount Desert.

. Charles F. Berhalter, the Republican nominee for House District 36, which encompasses several Penobscot Bay island communities including North Haven, Vinalhaven, Deer Isle and Stonington.

Dwayne Bickford, executive director of the Maine Republican Party, and Chris Harris, spokesman for the Maine Democratic Party, said they were confident replacements would be found for the 22 GOP and 14 Democratic candidates. The Green Independent Party also is seeking replacements for four candidates.

While the search for substitutes continues, some candidates are awaiting a court ruling to find out if they will be on the ballot. The Maine Supreme Judicial Court is weighing whether it has jurisdiction to determine two disputed Senate races and one House contest.

Included for the court’s potential consideration next week is an appeal by Democratic write-in candidate Kim Bagley of Machias, who needed 200 votes to get on the ballot. State election officials ruled she received 173. Bagley maintains a recount of 279 ballots for Senate District 29 should have identified 211 that were marked in a manner indicating that she was the voters’ choice.