Former Secretary of Administration and Finance Jay Gonzalez. (Photo by David L Ryan/The Boston Globe via Getty Images)

BOSTON (CBS/AP) — Republican Gov. Charlie Baker is facing his first official Democratic challenger in next year’s governor’s race.

Jay Gonzalez, the former budget chief for former Democratic Gov. Deval Patrick, announced Monday that he plans to challenge the popular incumbent.

Gonzalez said Massachusetts needs a governor who will stand up to Republican President Donald Trump and defend the state’s values. He faulted Baker, saying the governor too often sits on the political sidelines when we need him.

“I’m running because I think we need to lead again,” Gonzalez told WBZ NewsRadio 1030’s Carl Stevens Monday.

“There are too many people in our state, families, working families, who are still struggling to get ahead and there are too many people who need a governor who’s going to stand up and make sure they know that every single person in the state is included and is welcome and that governor’s going to be there to fight for them. And right now I don’t think we have a governor that’s doing that.”

The names of other potential Democratic challengers have surfaced, including Newton Mayor Setti Warren, but Gonzalez is the first to formally declare his candidacy.

Baker is widely expected to seek re-election in 2018, though he has yet to make any formal announcement.

Baker opposed Trump during last year’s election and refused to vote for him. He attended Trump’s inauguration, but has also spoken out against some of Trump’s steps since the election.

On Sunday, Baker released a statement opposing Trump’s actions on immigrants and refugees saying Massachusetts is a global community that benefits from the shared experiences of partners from around the world.

“The federal government’s recent decision puts this at risk and I believe focusing on countries’ predominant religions will not make the country safer as terrorists have showed they intend to strike from across the world.” Baker said. “The confusion for families is real. The unexpected disruption for law abiding people is real.”

#jay4ma: @MassGovernor "has sounded like Donald Trump. He opposed re-settling Syrian refugees..in Massachusetts." — Carl Stevens (@carlwbz) January 30, 2017

Gonzalez served in various capacities in state government including as Patrick’s secretary of administration and finance and as chairman of the Massachusetts Health Connector where he helped oversee the implementation of the state’s health care law.

He also served as chairman of the Massachusetts Board of Early Education and Care and co-chaired the Massachusetts Life Sciences Center.

Any Democrat hoping to unseat Baker faces a daunting political task. Polls have shown Baker as one of the most popular governors in the country. Baker also has a hefty $4.7 million in his campaign account.

But as a Republican in Massachusetts, Baker can take little for granted.

Despite his efforts to distance himself from Trump, Democrats are hoping the new year provides them with new ways to chip away at Baker’s popularity, in part by trying to tie him to Trump, who lost to Democrat Hillary Clinton by 27 points in Massachusetts during last year’s presidential race.

WBZ NewsRadio 1030’s Carl Stevens reports

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