Add another name to the lengthy list of potential GOP opponents for Sen. Blanche Lincoln (D-Ark.): Arkansas state Senate President Bob Johnson.

From the AP:
Arkansas Senate President Bob Johnson said Friday that he's considering challenging incumbent Democrat U.S. Sen. Blanche Lincoln in next year's primary.

Johnson told The Associated Press that's he's been encouraged to challenge Lincoln, who is seeking a third Senate term next year. Johnson said he doesn't have a timeline for deciding whether to challenge Lincoln.

"I'd be less than honest if I told you it hasn't surfaced in a number of circles," Johnson said. "I am weighing it very carefully."

Republicans have identified Lincoln as their top target on next year's ballot; five candidates have already announced they're running for the GOP Senate nomination. So far, no Democrats have said they're challenging Lincoln in the primary.

Johnson, who served as House speaker during the 1999 legislative session, has represented his north central Arkansas district in the state Senate since 2001.

Though the field is big, it is still without a big-name lawmaker. The current frontrunner is probably businessman and Mike Huckabee adviser Curtis Coleman. State Sen. Gilbert Baker is also considering the race.