A Washington, D.C.-based group is launching a campaign that seeks to link Republican U.S. Reps. Erik Paulsen and John Kline to the Tea Party.

Americans United for Change is trying to tie 47 swing-district Republicans around the nation, to the conservative movement with "Tea Stained," a legislative scorecard that ranks lawmakers by votes the group sees as aligned with Tea Party values.

The analysis includes 48 U.S. House votes, including votes to defund the Affordable Care Act and those taken during the government shutdown to fund some parts but not all of the government.

The group argues that Paulsen voted with the Tea Party 83 percent of the time in 2013 while Kline's loyalty score was slightly lower at 79 percent – and that their voting tendencies don't differ much from U.S. Rep. Michele Bachmann, founder of the congressional Tea Party caucus.

"Voters deserve better. Whether they embrace the Tea Party ideology or despise it or fall anywhere in between, they have a right to know where their elected representatives fall on the Tea Party spectrum - not where they say they fall, but how they actually vote," said Americans United for Change President Brad Woodhouse in a statement.

"What it proves, unfortunately for non-extremists who are represented by Republicans, is that there is no longer a meaningful distinction between the Tea Party and the Republican Party in American politics today."

The label may not stick for Kline and Paulsen. Neither is officially affiliated with the tea party movement.

Kline already has a Tea Party-backed candidate, David Gerson, challenging him for the Republican endorsement in the Second District, which covers the suburbs and exurbs south of the Twin Cities. Paulsen represents the Third District, which includes most of the western Minneapolis suburbs.

Amid the Tea Party's sagging national popularity, Americans United for Change views both Kline and Paulsen as vulnerable this election cycle because President Obama narrowly won both of the districts, which include a sizeable share of independent and Democratic voters, in 2012.

The scorecard is "highly unreliable at best," said Minnesota Republican Party Chairman Keith Downey. "Clearly, it's just a campaign tactic. If their point is that John Kline and Erik Paulsen voted pretty consistently against Obamacare, that's not a bad thing."

Kline and Paulsen did not respond to requests for comment.