The Senate voted Tuesday to confirm Rep. Hilda L. Solis , D-Calif., as secretary of Labor, despite Republican concerns about her pro-union voting record.

The 80-17 vote leaves two vacancies in President Obama’s Cabinet — Commerce secretary and Health and Human Services secretary. Solis was sworn in Tuesday evening.

While the final vote for Solis was decisive, it was not an overwhelming vote of confidence in the new Labor secretary. Only Treasury Secretary Timothy F. Geithner , confirmed by 60-34, and Attorney General Eric H. Holder Jr. , confirmed by 75-21, drew more “no” votes.

Solis — who resigned from the House after her confirmation, setting up a special election to replace her — was among the first to receive a nomination hearing before a Senate committee. But her bid hit several snags since she was first grilled Jan. 9 by the Health, Education, Labor and Pensions Committee, including a brush with tax debts, the issue that plagued Geithner.

Her husband, Sam Sayyad, paid off 16 years’ worth of tax liens against his business while Solis was being vetted by the committee. She also drew pointed questions about her affiliation with the pro-union organization American Rights at Work, for whom Solis served as treasurer while serving in Congress.

Republicans also accused Solis of a lack of candor about her position on such touchstone labor issues as a“card-check” bill to make it easier for unions to organize a workplace and state right-to-work laws.

Traditional partisan differences on such issues have only been exacerbated by the current economic climate. Business advocates and their Senate allies say measures to increase workers’ bargaining power would undermine employers already strained by the recession. Labor groups and their supporters see workers’ rights as a critical part of restoring the economy to health.

Solis has a well-documented track record of pro-labor positions. The daughter of union activists, she received a 97 percent approval rating from the AFL-CIO for her eight years in the House.

Nonetheless, she refused to state her views on specific issues when questioned during a committee hearing in January. That led Republicans to submit several additional rounds of questions to Solis that extended the panel’s review for weeks.

“This is not a nomination for a judicial position where a nominee quite understandably should not be expected to respond to hypotheticals involving cases that might come before her – this is a policy post, and policy questions deserve full answers from any nominee,” said committee ranking Republican Michael B. Enzi , R-Wyo.

Enzi added that he was concerned Solis lacked the management experience necessary to run a department with a budget of over $50 billion and more than 17,000 employees.

Enzi, however, ultimately supported Solis; 17 Republicans voted against her.

As Labor secretary, Solis will not only promote the administration’s policy on legislation but will also oversee programs and agencies within the department whose budgets and regulatory authority were scaled back under the Bush administration.