The effort builds on a poll released last week that shows Americans believe Republicans, more so than Democrats, are responsible for inaction in Washington.

Democratic Senatorial Campaign Committee spokesman Justin Barasky notes that McConnell has previously called himself the "proud guardian of gridlock," a comment for which Senate Majority Leader Harry ReidHarry ReidReid: Comey should be investigated in wake of Russia report Spokesman: NY Times ignored Reid's comments in pre-election story on Russia Senate passes dozens of bills on way out of town MORE (D-Nev.) hammered the Republican on Monday.

Mitch McConnellMitch McConnellRepublican wins La. Senate runoff in final 2016 race Heitkamp is Trump's top choice for Agriculture secretary: report Schumer calls for Senate probe into Russian interference MORE’s self-proclaimed moniker as the ‘proud guardian of gridlock’ has devastating consequences for Kentucky jobs, seniors, women, veterans, and businesses. As the walking talking embodiment of everything that’s wrong with Washington, Mitch McConnell is the number one reason for record breaking levels of obstruction and dysfunction,” Barasky said.

Party clash over the filibuster has reached a fever pitch in recent days, with Reid threatening to change Senate rules to eliminate the use of the procedural hurdle under certain circumstances.

The Senate will vote on a number of stalled nominations Tuesday morning, Republican approval of which Democrats say is necessary to avoid the so-called "nuclear option" to change Senate rules.

McConnell made those comments in 2005, under similar circumstances when Republicans, then the majority party in the Senate, were considering reforming the filibuster.

The debate has given Democrats opportunity to hammer Republicans for what they consider unprecedented obstruction. The DSCC highlights that since McConnell became minority leader in 2007, the Senate has seen an "unprecedented period of obstruction with a record 413 filibusters."

And McConnell's seat remains one of Democrats' most promising pickup opportunities in a map that looks increasingly problematic for the majority party.

Though Kentucky is a deep-red state on the presidential level, Democrats believe McConnell's unpopularity in the state, according to a handful of polls, and their recruit — popular Kentucky Secretary of State Alison Lundergan Grimes — makes the seat competitive.