The Republicans are determined to keep Scott Brown in his seat as U.S. Senator from Massachusetts, and, as with all seats in Congress, they play a cautious, watchful game. Republican party leaders know a Senator has to keep his constituents placated, so they allow votes that are contrary to the party’s position—but, in most cases, only when they know they can afford to lose a vote.

They know that Massachusetts is, in general, a progressive state that would throw out a Senator with right-wing views. They know Brown has serious opposition in popular consumer advocate Elizabeth Warren. So they’re all too willing to manage appearances so as to help Brown hang onto his reputation for being bipartisan and independent.

But Brown’s voting record doesn’t bear out the bipartisan image that’s brought some Democrats over to him, according to an analysis by ProgressMass done before the competition between Brown and Democrat Elizabeth Warren got hot and heavy, forcing Brown to play the bipartisan card more often.

ProgressMass, an admittedly “progressive” organization with a mission that includes “holding officials accountable,” tallied 53 roll-call votes by Brown in three types of situations: when the measure would pass on an up-or-down vote because it had the support of 50 Senators or more; when the GOP invoked procedures to require 60 votes for passage instead of 50, a simple majority; and when a majority of Republicans in the Senate opposed a measure.

In the case of measures supported by 50 or more Senators, Brown voted with Republicans to obstruct the legislation 40 out of 53 times, or in 75.5 percent of cases. Earlier—before Warren formed her exploratory committee last year—Brown voted to obstruct majority-supported legislation opposed by Republicans 30 out of 32 times.

So what laws did he help his party obstruct? “I know Scott Brown will fight for families,” says a woman in one of the latest Brown TV spots. Yet in 2010, Brown helped Republicans hold up the Paycheck Fairness Act, which would have helped victims of gender discimination get fair and equal wages. Also that year he helped slow down the Emergency Senior Citizens Relief Act, which authorized a one-time payment of $250 to Social Security recipients to make up for the lack of a cost-of-living increase.

Among other legislation that Brown helped the Republicans delay or kill:

*The DISCLOSE Act of 2010, written in response to the Citizens United decision. The law would have made it easier for the public to identify corporate and special-interest donors to national political campaigns.

*The Creating American Jobs and Ending Offshoring Act, which would have provided tax incentives to companies who replaced overseas workers with workers in the U.S., and removed incentives to outsource jobs.

*The Small Business Innovation Research/Small Business Technology Transfer Reauthorization Act of 2011, a bill Brown supported until the Republicans decided to support a competing bill.

*The Close Big Oil Tax Loopholes Act of 2011, which would have ended five tax subsidies for American oil companies. The savings would have gone to reduce the federal budget deficit.

For a more complete study of Brown’s record on obstructing legislation contrary to the spirit of bipartisanship, read the report at www.progressmass.org/press/new-study-progressmass-analysis-of-scott-browns-voting-record-reveals-highly-partisan-record-overwhe.html.