Could Missouri be the next Senate seat to fall in 2010?  Last year, Rep. Roy Blunt decided to challenge Democrat Robin Carnahan for the seat in what was called a battle of the dynasties, as both families have long political traditions in the Show-Me State.  Rasmussen initially had Carnahan barely in front of Blunt, but the latest poll of likely Missouri voters now shows Blunt with a six-point lead — and the Secretary of State slipping badly:

Republican Roy Blunt now holds a six-point lead over Democrat Robin Carnahan in Missouri’s race for the U.S. Senate.

A new Rasmussen Reports telephone survey of likely voters in the state finds Blunt ahead of Carnahan 49% to 43%. Three percent (3%) prefer some other candidate, and five percent (5%) are undecided.

The latest numbers mark a shift in Blunt’s favor from last month when Carnahan had a narrow 46% to 44% edge over her Republican rival. The candidates, both members of prominent Missouri political families, were tied at 46% apiece in September. As it has for other Democrats throughout the nation, the health care issue appears to be creating challenges for Carnahan. Just 37% of Missouri voters favor the health care plan proposed by President Obama and congressional Democrats, but 62% oppose it.

What’s causing the shift? The same reason Democrats lost the safest seat in the Senate earlier this week:

As it has for other Democrats throughout the nation, the health care issue appears to be creating challenges for Carnahan. Just 37% of Missouri voters favor the health care plan proposed by President Obama and congressional Democrats, but 62% oppose it.

Carnahan has some big problems in the internals. First, both candidates are well-known quantities in Missouri, with only 6% not having an opinion of Carnahan and 9% for Blunt.  Carnahan can only manage a 49% favorable rating, a danger sign for any candidate, while Blunt gets 56% — not great, but better than his opponent.  Oddly, Carnahan only gets a 51% favorable from women, while Blunt gets 56%, an unusual gender gap, although at the moment Carnahan edges Blunt with the female vote by two points.

The unaffiliated voters have broken hard for Blunt.  He has a 20-point lead, 52/32, among independent voters.  Furthermore, those voters are much more inclined to oppose ObamaCare, 74%/24%, so the remaining independents will almost all go Blunt’s way in a two-way general election race.  Blunt also gets 12% of Democrats to cross over.

The economy will probably be the deciding factor, at least after ObamaCare.  Only 7% of Democrats, 3% of Republicans, and 9% of independents rate the economic situation as “excellent” or “good”.  Majorities of all three rate it “poor”, the worst option in the survey, with 57% of independents giving that answer.  That doesn’t help Democrats in what will already be a tough election year.

This race looks increasingly like a Republican hold, which should surprise no one this year.

Update: D’oh!  Jefferson City is Missouri’s capital; Harry Truman hailed from Independence.  Forty lashes with a wet noodle for that gaffe.