Rasmussen polls typically look at likely voters. I've also noticed that the trends identified there seem to be a week or two ahead of Gallup and others in trending. So some of Rasmussen's latest polling results pose reasons for conservatives to be concerned.
After months of trailing, Obama is once again ahead of the generic Republican candidate. Of course that's a meaningless poll in and of itself. there won't be a generic Republican on the GOP ticket. It will be someone that the public gets to know. But the trend is what's worrisome. It means Obama has regained some traction.
That idea is reinforced in the Rasmussen approval index and overall job approval which show Obama trending upwards too.
Lastly, the generic congressional ballot from Rasmussen has the Democrats tied with the GOP for the first time in nearly two and a half years.
Alone, these could be regarded as statistical noise, taken together it might portend a trend.