A super PAC aligned with Senate Majority Leader Mitch McConnell released a new digital ad Tuesday attacking Montana Sen. Jon Tester.

The ad, the group's first of the cycle targeting the vulnerable Democrat in this year’s midterm elections, seeks to tie Tester to national party figures and calls him "just another Washington liberal." It's paid for by Senate Leadership Fund, the GOP's main Senate outside group, which is allied with McConnell. An SLF spokesman declined to say how much money the group spent on the ad (which was shared exclusively with RealClearPolitics), but said the digital release is running on social media and search websites targeting key voters.

The ad begins by mocking Tester's well-known flattop haircut, with a narrator saying, "A crew cut doesn't make you a Montana conservative, Jon."

The ad then ties Tester to four Democratic figures Republicans frequently use as bogeymen in campaign messaging: Sens. Elizabeth Warren and Bernie Sanders, House Minority Leader Nancy Pelosi and former President Obama. It criticizes Tester for voting against a short-term government funding bill last month, saying he joined Warren to shut down the government and sided with Sanders "to put illegal immigrants over sick kids in Montana." Tester has said his vote against the funding bill was not about immigration, but because the bill lacked funding for community health centers in his state.

The ad also criticizes him for siding with Obama at a higher rate than President Trump, saying he voted with Obama 93 percent of the time but -- according to tracking data from the website FiveThirtyEight -- voted with Trump 37 percent of the time.

Trump won Montana by 20 percentage points in the 2016 election, and Tester is one of 10 Democrats up for re-election this year in states the president carried.