An internal poll released by Democratic Rep. Joe Donnelly's campaign shows him in a dead heat with GOP Treasurer Richard Mourdock in the Indiana Senate race.
The poll was conducted for the congressman's campaign by Global Strategy Group, and measures both a head-to-head matchup between Donnelly and Mourdock and a three-way race with Libertarian candidate Andrew Horning. Donnelly leads Mourdock 43 percent to 41 percent in the two-way race. In the three-way contest, Donnelly also edges Mourdock by two points (40 percent to 38 percent), with Horning taking 8 percent of the vote.
Donnelly holds a lead among independent voters under both scenarios: In a three-way race, he leads Mourdock by 5 points, and by 6 points in a head-to-head (each candidate's specific numbers are not given).
For months, most polls have showed a tight contest in Indiana, where Mourdock defeated Sen. Richard Lugar in a Republican primary earlier this year. Mitt Romney is expected to easily win the state, and the GOP presidential nominee cut an ad for Mourdock that the Senate candidate's campaign released Monday.
The Global Strategy Group poll was conducted between October 17-21 and surveyed 603 likely voters. The margin of error is plus-or-minus 4 percentage points.