Chris Fierro, District Director for Rhode Island First District Congressman David Cicilline, tweeted this following a Cicilline fundraiser held last night…

Leaving a fantastic event for @davidcicilline — strong support; full room with @Angel_Taveras @LincolnChafee @GinaRaimondo and many more!

Mayor Taveras and Treasurer Raimondo were mentioned in earlier news reports (WRNI’s Ian Donnis, WPRI’s Ted Nesi) as members of the host committee for this event and have declared various level of public support for Cicilline’s reelection (in Raimondo’s case, her support is not an “endorsement”), but the list of names on the host committee reported by GoLocalProv’s Dan McGowan and WRNI’s Ian Donnis did not include Governor Chafee and, as far as I know, this is the first mention of Governor Chafee publicly supporting Congressman Cicilline’s reelection.
UPDATE:
According to Ted Nesi, fresh from the taping of this week’s Newsmakers for WPRI-TV (CBS 12), it’s a full-blown endorsement…

Gov. Lincoln Chafee said Friday he’s endorsing the freshman Democrat for reelection, the morning after he attended a Cicilline fundraiser in Providence whose host committee included Providence Mayor Angel Taveras and Treasurer Gina Raimondo.
“A lot of the criticism leveled against Congressman Cicilline’s time as mayor I think is unfounded, because he suffered $30 million in [state aid] cuts, and that’s what we’re talking about,”