Arkansas Lt. Gov. Bill Halter with a shocker this morning: He said he will challenge Democratic Sen. Blanche Lincoln (Ark.) in a primary this year.

Halter's name seems to come up whenever there is a major office up for election, but in a video on his website, he said he's taking the plunge.

Look for Halter to run more of an anti-Washington campaign, as opposed to going after Lincoln on ideological grounds.

She becomes the fourth incumbent Democratic senator to draw a primary challenge this cycle, joining Sens. Arlen Specter (D-Pa.) and Michael Bennet (D-Colo.) and likely Sen. Kirsten Gillibrand (D-N.Y.).