These days Republican candidate Mike Huckabee is asked more about when he will quit the GOP race and why he hasn’t already ended his presidential bid more than any questions about policy. Ignoring frequent calls for his exit, Huckabee has campaigned on in the Badger State this past week. The former Arkansas Governor is now locked in a tight battle with John McCain in Wisconsin, according to an American Research Group (ARG) poll conducted of 600 likely Republican primary voters on February 15-16.

The ARG poll gives McCain a 46 to 42 percent edge over Huckabee, with 4 percent giving their support to Ron Paul. Seven percent of likely GOP voters are undecided. After Super Tuesday, but before Mitt Romney had announced his withdrawal from the race, Huckabee was only polling at 4 percent in Wisconsin, with McCain at 51 percent, Romney at 29 percent, and Paul at 7 percent (ARG, February 6-7).

Huckabee is hoping for a big independent vote for Obama on the Democratic side of the ticket on Tuesday, draining McCain’s base (Wisconsin’s contest is an open primary). According to the ARG poll, Ron Paul also benefits from independents voting in the GOP primary (11 percent).

On the Democratic side, ARG continues to show Clinton with a lead—this time by 6 points, 49 to 43 percent; ARG’s poll after Super Tuesday showed Clinton with a 50 to 41 percent lead. All other public polls give Obama a 4 to 5 point lead.

It should be noted ARG has overestimated Clinton’s support (and underestimated support for Obama) in several races in polls ending the day before the following contests:

Iowa
ARG: Clinton +9
Caucus results: Obama +9

South Carolina
ARG: Obama +3
Primary results: Obama +28

Michigan
ARG: Clinton +25
Primary results: Clinton +15

Florida
ARG: Clinton +30
Primary results: Clinton +17

Tennessee
ARG: Clinton +22
Primary results: Clinton +13

Maryland
ARG: Obama +17
Primary results: Obama +23

Virginia
ARG: Obama +17
Primary results: Obama +29

ARG – like most pollsters – overestimated support for Obama in surveys before the California and New Hampshire primaries.