The Democratically-aligned group End Citizens United on Tuesday launched a $50,000 digital advertising campaign aimed at unseating Senate Majority Leader Mitch McConnell in Kentucky — before McConnell even has a credible challenger.

The ad, End Citizens United’s first independent expenditure of the 2020 cycle, highlights McConnell’s work to block campaign finance reform measures in Washington.

“Mitch McConnell has a long history of making sure politicians can be bought,” a male voice says, as pictures of McConnell spanning his 35-year Senate career flash on the screen. “Now Mitch is blocking the most important anti-political corruption legislation since Watergate.”

McConnell is a top target for Democrats, who are still seething over his 2016 move to block former President Barack Obama’s Supreme Court nominee Merrick Garland. But so far, no big-name candidates have taken on the fight. Inside Elections with Nathan L. Gonzales rates the race Solid Republican.

The ad is a reference to McConnell’s early years spearheading Republican resistance to a string of campaign finance reform proposals and his recent vow not to allow a Senate vote on Democrats’ signature congressional reform bill, HR-1.