That was one eye-catching finding overnight from the latest Suffolk University/WHDH-TV poll about the race.

With six months to go, only 5 percent of voters are undecided and able to be convinced by it all.

Consider this as you brace for a multimillion-dollar US Senate race this fall that hijacks the commercials amid your favorite TV shows, fills the newspaper, and is propelled by verbal barrages between Republican Scott Brown and Democrat Elizabeth Warren.

Brown and Warren were in a statistical tie, with the incumbent senator at 48 percent and the Harvard Law School professor at 47 percent. That is not necessarily good news for Brown, since he clearly led Warren 49 percent to 40 percent in a similar Suffolk/7News poll in February.


At that time, though, the number of undecided voters was 9 percent. Now, after both candidates have begun advertising and the campaign has been filled with talk of basketball shots and Native American heritage, the size of the undecided vote has fallen to 5 percent.

That means opinions are calcifying even before the worst of the head-to-head campaign begins. And that is a reflection of omnipresent news coverage from an array of digital sources, as well as the intensity of passion by voters favoring a check-and-balance on the state’s Democratic congressional delegation.

It also reflects the passion of those opposed to the Republican who replaced a Democratic icon, the late Edward M. Kennedy, in the US Senate.

The poll comes at an important time in the race, after Brown and Warren began to engage and her early headlines about large fund-raising and institutional support were undercut by his suggestion that she used a bogus claim of Native American heritage to advance in her academic career.

The Warren campaign polled the issue internally last week, and the Democratic Senatorial Campaign Committee - charged with keeping a Democratic majority in the upper chamber of Congress - took the unusual step of releasing its own poll findings on Tuesday.


That the DSCC commissioned such a survey itself attested to concern in the capital that one of the Democrats’ best pickup opportunities might be at risk.

Coming little more than two years after Brown stunned the Washington establishment by beating Attorney General Martha Coakley in a special election to succeed Kennedy, national Democrats have no appetite to be surprised again.

The Suffolk poll, however, comes from a university without a campaign’s or a party’s vested interest in the outcome of the race.

For that reason, its findings bear special scrutiny.

First, the poll challenged the long-running statement that Brown is the most popular politician in the state.

Governor Deval Patrick had a favorable rating of 60 percent, up from 54 percent in February. His unfavorable rating was down to 32 percent, from 37 percent this winter. Coakley herself topped Brown in a recent Globe survey.

Brown had a favorable rating of 58 percent, up from 52 percent in February. His disapproval rating was static at 28 percent - a good sign.

Warren had a favorable rating of 43 percent, up 8 points from 35 percent in February. But her unfavorable rating has also risen: from 28 percent to 33 percent in the latest survey.

That would suggest that Brown’s effort to raise character questions may be working. It could also mean that some voters are getting turned off as they hear her ads.


(Pity Mitt Romney. The former Massachusetts governor has seen his already bad favorability rating worsen since he has secured the Republican presidential nomination. It was 41 percent favorable/47 percent unfavorable in February; now it’s 36/54. That explains why he will spend little, if any, time campaigning in the Bay State the rest of this year.)

The idea that Brown’s ads may be working is reflected in the answers to another set of poll questions.

When voters were asked to list the first word that came to mind when they thought of Brown, “Republican” topped the list at 10 percent, followed by “independent” and “honest” at 8 percent each.

For Warren, “smart/well-educated” topped the list at 7 percent. But “don’t like” was second at 6 percent, while “liberal” and “dishonest” tied with “Democrat” and “like her” at 4 percent.

Brown’s argument that he is not only a moderate and an independent but also a check-and-balance on the Democrats in the delegation was also backed by another question.

Asked if the state benefits from having both a Democratic and a Republican senator, 56 percent said yes while 38 percent said no.

The idea that Warren is also being boosted by those with a fervor to displace Brown was supported by the answers to a final pair of questions.

The people who said they planned to vote for the senator were asked what was driving their decision. Ninety-two percent said it was their support of Brown, while 8 percent said it was their opposition to Warren.


By contrast, 77 percent of Warren’s backers said they were for her; a sizable 23 percent said their vote was being driven by their opposition to Brown.

The poll made one other thing clear: this campaign is almost assuredly coming down to a race between Brown and Warren. She is still likely to face a primary challenge in September from North Shore immigration attorney Marisa DeFranco, but the poll found that Warren led DeFranco 49 percent to 28 percent, with 22 percent undecided.

That means Brown and Warren are destined to spend the fall battling for a relatively small number of undecided voters.

The same phenomenon is shaping up nationally, with a group of king-making voters poised to settle the presidential race between Barack Obama and Mitt Romney.

For everyone else headed to the ballot box, the intervening campaign will be background noise.

Glen Johnson can be reached at johnson@globe.com. Follow him on Twitter @globeglen.