Voters in states with “toss-up” Senate races will look heavily to a looming battle over income taxes, a GOP poll argued Monday.

Resurgent Republic, a research group founded by former Republican National Committee (RNC) Chairman Ed Gillespie, released a poll stating that voters from states undergoing “toss-up” Senate races in November largely oppose letting the Bush-era tax cuts expire at the end of the year.

Fifty-five percent said they would be less likely to vote for Democratic candidates in House or Senate races if Democrats failed to stop or delay tax increases before the November elections, the poll found. Twenty-one percent said they would be more likely to vote for a Democrat.

The survey polled 1,000 likely voters from 12 states facing uncertain elections, as listed by Cook Political Report. Those states included Arkansas, California, Colorado, Florida, Illinois, Kentucky, Missouri, New Hampshire, Nevada, Ohio, Pennsylvania and Washington.

Three-quarters of Republican voters and two-thirds of both independents and Democrats who were surveyed said they were concerned that important legislative issues won’t be addressed until after the November elections, in a lame-duck session of Congress.

Sixty-three percent said that they would be less likely to vote for their member of Congress if he or she refused to rule out voting on hot-button issues like tax rate changes, immigration reform, energy legislation or card check after the November elections.

The poll, conducted by Ayres, McHenry & Associates between July 17-20, has an overall 3.1 percent margin of error, a 5.66 percent margin of error for Republican subsamples, a 5.17 percent margin of error for independent subsamples, and a 5.39 percent margin of error for Democratic subsamples.