Conservative watchdog flunks Democrats

To calculate its report card, NTU sifted through more than 500 votes from 2011 — 337 in the House and 234 in the Senate — that it said could have considerable impact on taxes, spending or regulatory policy.

With congressional approval ratings hitting historic lows recently, the NTU report card also illustrated the ideological differences between the Democrats and Republicans, even as the two parties have come together of late on a small business and bill to curb insider trading by lawmakers.

In the Senate, NTU gave only 17 lawmakers grades below a B and above an F. The four senators who caucus with the Democrats and did not receive a failing grade — Joe Lieberman (Conn.), Claire McCaskillClaire McCaskillMcCaskill offers Trump 'Mean Girls' advice Trump's taxes bump Miss Universe from headlines Dem on NYT report: Trump 'walks away with a golden ticket' MORE (Mo.), Ben Nelson (Neb.) and Joe ManchinJoe ManchinTrump questions hound endangered Republican Dems to McConnell: Pass 'clean' extension of Iran sanctions Convicted ex-coal boss says he’s a ‘political prisoner’ MORE (W.Va.) — all received Ds.

The scores were a bit less polarized in the House, but the six House Democrats from Maryland and the 10 from Massachusetts all received failing grades. The five Republicans from South Carolina, meanwhile, all received at least a B+.

Sen. Tom CoburnTom CoburnRyan calls out GOP in anti-poverty fight The Trail 2016: Words matter Ex-Sen. Coburn: I won’t challenge Trump, I’ll vote for him MORE (R-Okla.) received a score of 96 percent, the highest in either chamber, with Sen. Ron JohnsonRon JohnsonMcCain: Accepting election results is 'American way' Wisconsin poll: Clinton has 7-point lead on Trump Cruz: Voter fraud a challenge MORE (R-Wis.) just one percentage point behind.

Around 10 Republicans in the House got at least a 90 percent score from NTU.