Coming off of a landslide victory in the Democratic primary, many observers predicted Governor Joe Manchin was on a fast track to the nation's capital.

But a new Rasmussen poll shows Manchin may have a fight on his hands for the unexpired term of the late Robert C. Byrd.

In a survey of 500 likely voters, Manchin was favored over Republican John Raese 48 to 42 percent. National political commentator Dick Morris says that shows chinks in Manchin's armor.

Since declaring about a month ago to run, Raese has waged aggressive television and radio ad campaigns.

Meanwhile, Manchin has been relatively quiet. His supporters say the Rasmussen poll isn't consistent with other numbers they've seen, and that the polling organization leans toward the GOP.

But Raese counters that he offers voters a clear choice in November.

The same poll shows Manchin with a more than 70 percent approval rating. But Morris says Washington is a very different stage and setting than Charleston.