Republicans lacks candidates for three Maine Senate races, but that's not expected to dramatically change the heated fight for the upper chamber.

Republicans, who hold an 18-17 majority in the Maine Senate, won’t field candidates in three Senate races this fall.

Monday was the deadline for party county caucuses to select replacements for legislative candidates who withdrew after meeting the March 15 deadline to earn their parties a spot on the November general election ballot. Republicans did not find replacements for candidates in three Portland-area Senate districts.

But that should not greatly alter the campaign landscape leading up to what bodes to be a heated competition for control of the upper chamber. All three districts in which Republicans chose not to enter a candidate tilt solidly Democratic.

Sen. Bill Diamond, D-Windham, whose legislative career dates to the 1970s, has rarely faced serious competition in District 26, which covers the Sebago Lakes region. He’s on a clear path to the third term of his latest stint in the Senate.

Sen. Mark Dion, D-Portland, ran for governor, creating an open seat in Senate District 28. Rep. Heather Sanborn of Portland won the Democratic primary against Portland City Councilor Jill Duson, and now has no ballot opposition for the general election after Republicans failed to find a replacement for Patrick Gilman Martin.

Republicans also won’t field a candidate in Senate District 27, where independent Crystal Canney will challenge incumbent Portland Democrat Ben Chipman, who was first elected to the Maine House as an independent but who joined the Maine Democratic Party in 2015. Chipman is seeking his second term in the Senate.

Democrats have candidates on the ballot in all 35 Senate elections. Republicans replaced six Senate candidates who withdrew.

Late additions for Republicans include Stavros Mendros, a controversial figure whose past work on campaigns has drawn sanctions from the Maine Ethics Commission, and James LaBrecque, who has advised Gov. Paul LePage on energy issues during parts of the governor’s tenure.

Mendros will challenge incumbent Sen. Justin Chenette, D-Saco, in District 31, LaBrecque will take on three-term incumbent Sen. Geoff Gratwick, D-Bangor, in District 9.

Senate Republicans have a good track record with replacement candidates. Sens. Scott Cyrway of Benton, David Woodsome of North Waterboro and Lisa Keim of Dixfield all won election as replacements. All are seen as strong candidates for re-election in 2018.

In Maine House races, Republicans and Democrats each didn’t find replacement candidates for three races.

Republicans won’t field candidates in House District 34 covering part of Westbrook, House District 43 covering parts of Falmouth and Portland, and House District 120, which is represented by former Republican Norm Higgins, who became an independent in 2017.

Democrats will not have candidates on the ballot in House District 17 in York County, House District 77 covering Oakland and part of Sidney, and House District 104, which includes Charleston, Dexter, Exeter, Garland and Stetson.

Democrats hold a 74-70 plurality in the lower chamber, with six independents and one voting Green Independent Party member.

Sept. 7 is the deadline for declared write-in candidates.

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