The phrase "a relatively narrow base" is correct and usable in written English.
It can be used to describe a situation, concept, or object that has a limited or restricted foundation or support.
Example: "The new policy was built on a relatively narrow base of evidence, which raised concerns among the experts."
Alternatives: "a limited foundation" or "a small base of support".
Mrs. Clinton, though, depended even more heavily on a relatively narrow base of wealthy and committed donors who contributed about $19 million.
Since winning re-election as Gujarat's chief minister, in December, he has increasingly turned his attention to national matters, to building his position in the party and getting allies elevated to leading positions within it.His challenge, as ever, is to spread his appeal beyond a relatively narrow base of fervent supporters, who predominate in India's north and west.
There is no easy solution for the lack of mature liquids or the fact that what is available is coming from a relatively narrow base of producers.
Incoming White House Chief of Staff Andy Card Andy Card used to represent the auto industry in Washington, so the most senior officials in this Administration share a relatively narrow base of experience in business.
Two of Mrs. Schroeder's most serious concerns about becoming a Presidential candidate involved fears that she would be perceived largely as a feminist candidate and, relying on this relatively narrow base, would be unable to make a respectable showing.
The reports also indicate the relatively narrow base of big donors behind each of the Republican primary's two fund-raising leaders.
But fund-raisers for three public charities, who spoke on condition that their institutions not be identified, said that the practice was on the rise as charities competed for gifts among the relatively narrow base of very wealthy donors.
The quadrate ramus is broken away, apart from its relatively narrow base (Figures 3B and C).
Although this breeding strategy has been successful in alleviating key production constraints, the unintended consequence is that many current varieties in Southeast Asia and South Asia have a relatively narrow genetic base.
The disomic polyploid nature of cotton poses a particular challenge in that most loci are duplicated, and breeding germplasm is derived from a relatively narrow genetic base [ 17, 18].
Interestingly, the variable genome in Bm encompassed a larger portion of the genome (33 41%) than in Bp (20.6%), suggesting that even with a relatively narrow genetic base, the genome of Bm is continuing to change, albeit without actual gain of genes to the pan-genome.
