Sen. Susan Collins, R-Maine, chair of the Senate Appropriations Committee, heads to the chamber before June 4 votes on the immigration enforcement funding package, at the Capitol in Washington. (J. Scott Applewhite/Associated Press) PORTLAND — This election year is déjà vu for Sen. Susan Collins — the Maine Republican is running for reelection as Democrats pin their hopes on a new candidate to defeat her. Last time, it was state lawmaker Sara Gideon.