WASHINGTON—In a party-line vote, the Senate approved Kathy Kraninger on Thursday to run the Consumer Financial Protection Bureau, giving the federal agency, which has been caught in a bitter partisan fight, its first full-time Trump-appointed leader.

Ms. Kraninger, a White House budget official with little experience in financial regulation, will succeed CFPB acting director Mick Mulvaney and is expected to continue changes he introduced easing oversight of financial companies, drawing opposition from Democrats and consumer advocates. She is a close associate of Mr. Mulvaney’s, having worked under him at the Office of Management and Budget, where Mr. Mulvaney also serves as White House budget chief.

“I think we will see more of the same that’s been happening under acting director Mulvaney,” said Dan Berger, president of the National Association of Federally-Insured Credit Unions, a trade group, adding he welcomes the prospect of further rollbacks of financial rules. “We look forward to working with director Kraninger.”

At her July confirmation hearing, Ms. Kraninger, 43, pledged to pursue the “proper balancing of all interests,” empowering consumers to make “good choices” and markets to stay competitive. She said her top priorities included a thorough analysis of the cost of regulations on businesses and consumers, limiting government collection of consumer data and aggressive enforcement actions against “bad actors” engaging in fraudulent activities.

The Senate voted 50-49 to confirm her for a five-year term to lead the agency, with all Democrats opposing her. Sen. Thom Tillis (R., N.C.) didn’t vote.