Toehold refers to a small advantage or foothold gained in a situation. It's like a starting point or a small step forward that allows further progress or control. Full definition
An article in the May 23, 2001, edition of Education Week («New Accreditor Gaining Toehold in Teacher Ed.») (edweek.org)
His party has only the barest of majorities in the chamber, which is its only toehold on political power statewide. (nytimes.com)
For Republicans, who are keeping their last toehold of statewide power with Felder's help, his decision to stay put is an obviously welcome well, even as they brace for a potential Democratic wave year. (nystateofpolitics.com)