Governor Charlie Baker's announcement Tuesday that he will run for another term in 2018 is no surprise, although it has historic significance for Massachusetts — especially if he sticks around for his entire second term.

Mr. Baker is the first Republican Massachusetts governor since William Weld in 1994 to run for a second term. Mr. Weld resigned to become ambassador to Mexico under President Clinton, a move that was blocked by arch-conservative North Carolina Senator Jesse Helms. His successor, the late Paul Cellucci, who was Mr. Weld's lieutenant governor, left the State House to become ambassador to Canada, opening the door for Berkshire native Jane Swift to briefly serve as acting governor. She was elbowed aside by Mitt Romney, who served one term before running for president as the Republican nominee. Mr. Baker has said he has no political ambitions beyond serving as governor.

Governor Baker and Lieutenant Governor Karyn Polito, who will also run for re-election, are the only prominent Republicans in state and federal politics in Massachusetts. The entire congressional delegation is Democratic and Democrats dominate the state Legislature. Nonetheless, the governor enters the 2018 election year in a position of considerable strength. His approval numbers are consistently high and among the highest of governors nationwide. A fiscal conservative who is liberal on social issues, the governor has struck a balance that works in Massachusetts.

Money talks loudly in politics and the governor has accumulated a campaign war chest of $6.9 million and counting and has the state party apparatus behind him. His three announced Democratic rivals, Newton Mayor Setti Warren, environmental activist Robert Massie, and former state budget chief Jay Gonzalez, don't have those financial resources and none will have the Democratic Party in full support until after next fall's primary.

In terms of the Berkshires, Mr. Baker did not fare well in his two runs for governor, though in fairness both opponents enjoyed something of a home court advantage. Former Governor Deval Patrick, who defeated Mr. Baker, has a home in Richmond, and Martha Coakley is a native of North Adams and a graduate of Williams College. None of the three Democratic candidates has Berkshire roots, although Mr. Warren in particular has been working to establish connections with Democratic officials and voters in the county.

Those same polls that attest to the governor's popularity reveal that Republican President Donald Trump is highly unpopular in the state, as is the Republican congressional agenda. The Democratic candidates and the state party have and will continue to try to tie Governor Baker to the president and to D.C. Republicans but the task will be difficult. The governor has criticized the president for his shameful antics and statements and came out against both the attempts to dismantle the Affordable Care Act and pass a tax bill that is irresponsible and unfair to the middle class championed by Mr. Trump and D.C. Republicans. Massachusetts is a politically savvy state that can tell one Republican from another and is accustomed to putting a Republican atop the executive branch.

To win, Democrats will have to develop a coherent economic policy that contrasts with that of the governor. In so doing, they will ideally generate a debate on the issues that will prove beneficial to voters. The negative coattails of Mr. Trump and D.C. Republicans won't be enough for Democrats to regain the governorship.