\begin{table}[htbp] 
\centering 
\caption{\bf Within-Pool Comparisons: NP-Score of State Legislators Who Run vs. Those Who Do Not, DV = Dummy of Ideology} 
\label{tbl_main_regressions_run_33_dummy} 
\begin{tabular}{lcccccc} 
\toprule\toprule 
& \multicolumn{3}{c}{Democrats} & \multicolumn{3}{c}{~Republicans} \\ [.05in] 
Sample                 & Coeff.  & Std. Error  &  \# Obs.  & ~~Coeff.  &  Std. Error  &  \# Obs.  \\ [.01in] 
\midrule 
All pools              & 0.002 & (0.024) & [3898] & ~~0.082 & (0.028) & [5993] \\ [.01in] 
Open seats             & 0.020 & (0.027) & [2104] & ~~0.094 & (0.029) & [3001] \\ [.01in] 
Safe districts         & -0.013 & (0.030) & [1718] & ~~0.103 & (0.037) & [3358] \\ [.01in] 
Competitive districts  & 0.049 & (0.047) & [1169] & ~~0.082 & (0.039) & [2066] \\ [.01in] 
\bottomrule 
\end{tabular} 
\end{table} 
