Former Wisconsin Gov. Tommy Thompson (R) holds leads in both his Senate primary and the general election, according to a new poll from Marquette University.

Thompson is benefitting from a fractured primary field: While he's only at 34 percent support in the poll, three other candidates split the rest of the field, with former Rep. Mark Neumann (R-Wis.) at 16 percent support, businessman Eric Hovde pulling 14 percent and Wisconsin state Assembly Speaker Jeff Fitzgerald at 10 percent. The 34 percent support is actually Thompson's lowest tally in any poll in the last year, but the 18-point lead is his largest in that period.

Those numbers could tighten: Hovde has been spending his own money freely on ads since his recent entrance into the race, and was little-known by voters until recently. If his numbers keep climbing he could be a real threat to Thompson. Neumann has the backing of the fiscally conservative Club for Growth, which plans to attack Thompson's record and could do a lot of damage to the front-runner.

Thompson also leads Rep. Tammy Baldwin (D-Wis.) by 49 to 41 percent. Baldwin is tied with Neumann and holds single-digit leads over Hovde and Fitzgerald.

Wisconsin voters have been mostly focused on the state's recent gubernatorial recall and are just beginning to tune in to this race, so these numbers may still be as much a reflection of name recognition than of true support. It'll be a long, hot summer for the former governor — but these poll numbers show that unless some of his opponents' support collapses he could win the primary despite their attacks.

The poll was conducted from June 13 through June 16. The general election numbers have a margin of error of plus or minus 4.1 percentage points, while the primary's margin of error is plus or minus 5.4 percentage points.