Next year's gubernatorial contest in Massachusetts is tighter than ever, even though it's now a three-way race.

A new Rasmussen Reports telephone survey in Massachusetts finds incumbent Democratic Governor Deval Patrick holding on to roughly one-third of the vote no matter which of the most prominent Republican hopefuls is in the race. The governor posts a single-digit lead in both scenarios, but his challengers are gaining.

With businessman Christy Mihos as the GOP gubernatorial candidate, Patrick captures 32% of the vote. Independent candidate Tim Cahill gets 28% and Mihos earns 26%. Fourteen percent (14%) are undecided.

Patrick wins with 33% of the vote if health care executive Charlie Baker is the Republican nominee. In that scenario, the Republican candidate places second as Baker picks up 28% and Cahill 25%. Again, 14% are undecided.

A month ago, Patrick earned 34% of the vote in both scenarios. This suggests that the race for now is a referendum on the incumbent rather than a choice between competing alternatives.

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In late August, before Cahill joined the race, Patrick trailed Mihos by five points – 40% to 35% - and was virtually tied with Baker.

Cahill, a former Democrat, takes roughly a quarter of the Democratic vote away from Patrick regardless of which Republican is in the race.

Thirteen percent (13%) of Massachusetts voters now have a very favorable opinion of Patrick, who is serving his first term as governor. But more than twice as many (31%) view him very unfavorably.

Mihos is seen very favorably by 10% and very unfavorably by the same number (10%). Baker’s very favorables total 11%, while his very unfavorables are eight percent (8%).

Cahill, the state treasurer who was elected as a Democrat but resigned from the party this summer, is regarded very favorably by 10% and very unfavorably by eight percent (8%).

At this very early stage of the campaign, Rasmussen Reports considers the very favorable and very unfavorable figures more significant than the overall favorability totals. These numbers are little changed for all four candidates from a month ago.

Just 34% of voters in the state now approve of Patrick’s performance as governor, down nine points from October, while 64% disapprove. But unchanged is the finding that those who strongly disapprove outnumber those who strongly approve by more than three-to-one – 37% to 11%.

Fifty-five percent (55%) approve of the job President Obama is doing. Thirty-one percent (31%) strongly approve, but that’s down six points from last month.

Overall, 44% of Bay State voters disapprove of the president’s job performance, including 35% who strongly disapprove. Massachusetts voters continue to give Obama better job approval ratings that voters nationally in the Rasmussen Reports daily Presidential Tracking Poll.

Attorney General Martha Coakley remains well ahead among likely Democratic Primary voters in Massachusetts in the race to fill the U.S. Senate seat of the late Edward M. Kennedy. Democrats and Republicans will pick their respective candidates for the January 19 special Senate election in party primaries on December 8.

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