A new Siena poll suggests that Democrats are catching up in the March 31 special election for Kirsten Gillibrand's former House seat in upstate New York.

Republican candidate Jim Tedisco, who started out with much higher name recognition as the state Assembly minority leader, now leads Democratic businessman Scott Murphy by 45%-41%, with a ±3.7% margin of error. Two weeks ago, Tedisco had a much stronger lead of 46%-34%.

At first glance, it might look like Democratic-leaning undecideds are quickly breaking into the Dem column as the candidates become better known. But the internals actually paint a much more complex picture.

Two weeks ago, Tedisco led 45%-31% among independents. But Murphy has turned that around, and now leads among indies by 43%-37%. What this suggests is that the Dem attacks against Tedisco -- mainly targeting his refusal to take a firm position on the stimulus bill -- could be having their intended effect.